A relevant discussion of this question with some interesting examples can be found in [Calboli, Gualtiero (2009: 145-146). "Latin Syntax and Greek". In Philip Baldi & Pierluigi Cuzzolin (eds.). _New Perspectives on Historical Latin Syntax_ vol. 1,pp. 65–193. Berlin-New York: De Gruyter][1]. Here is the relevant quote (bold mine: Mitomino): 

>"_TP Sulp._ 51 Tab. II3 (_graphio, script. interior_) (...): _**que ominia** / possita habeo penes me in horreis Bassianis / puplicis Putolanorum **que** ob omini / ui periculo meo **est** [[dico]] fateor. / Actum Putolis_. 
'all these wares I have in my possession in public Bassian stores of Pozzuoli. These wares are free from every danger as I myself confirm on my own responsibility. Done in Pozzuoli'

>_TP Sulp._ 52 Tab. II3 (_graphio, script. interior_) (...): _**que ominia** ab omini // ui priculo meo **est** fator. (S) Actum Putolis_ 


> In Calboli (1999: 342), I explained the syntagm **_omina_ [sic] ... _est_ as a Graecism** resulting from the continuous commercial contact of Eunus with Greek traders. Perhaps C. Eunus was ignorant of Latin grammar but knew the prestigious position of Greek, imitated by Latin authors and poets, and had no reason to avoid a construction his Greek customers used. Petronius 71,10: **_faciatur, si tibi uidetur, et triclinia_** provides a parallel from a commercial environment. This example is rejected by [Hofmann & Szantyr: (1972: 431)][2], but they give others from Late Latin authors, such as Comm. _instr_: 1,34,18: **_aurea...ueniet tibi saecla_** 'the golden age will come to you', 2,1,15: **_ut mysteria...omnia...compleatur_** 'to accomplish all the mysteries', and _Chiron_. 399: **_ea uitia difficiliter uincitur_** 'these faults it is difficult to correct'. More examples are given by [Baehrens][3](1912: 483-496), who tried to demonstrate that this construction was native to Latin, because Latin had the same possibility of combining a neuter plural with a singular verb as Greek. A possible epigraphic example appears in the _Année Épigraphique_ (1987/974 [Aegyptus 161]: **_principia a nouo aed[ifi]catum est_** (see [Galdi 2004: 139][4])".

Concerning the first example above, it should be pointed out that an alternative proposal has been given in the specialized literature: cf.  [Adams (2016)][5]: "Another possibility is that _est_ represents a constructio ad sensum, with the collectivity that precedes inspiring a singular verb. The neuter plural _omnia_, which occurs in the preceding clause with _quae_, is sometimes treated as a collective singular, and not only in late Latin".    

Furthermore, in her study on Latin teaching materials in Antiquity [Dickey (2010: 193)][6] also provides an attested example on the influence of the rule of Greek at issue here on Latin. NB: Dickey's article is downloadable (bold mine: Mitomino) 

>"The person who provided this inflectional information, moreover, was not fully competent in Latin. In line 9 he uses a singular verb with a neuter plural subject: _**horum duorum cetera ut**_ **Cato** _**declinatur**_. In Latin of all periods plural subjects require plural verbs, regardless of their gender, but in classical Greek a neuter plural [subject] does indeed take a singular [verb] (...) The provider of this inflectional information must therefore have himself been a well-educated Greek speaker whose Latin studies had not yet progressed to a very high level: he knew the rule that in formal written language a neuter plural subject takes a singular verb, but he did not grasp that that refinement did not apply to Latin".

Admittedly, it is a bit funny to compare the perspective of "a well-educated Greek speaker whose Latin studies had not yet progressed to a very high level" with the one given in the question above on "educated Romans who liked to imitate Greek writing". However, it could well be the case that, after all, the one who used, let's say, _omnia fluit_ instead of _cuncta fluunt_ could  be considered by "educated Romans" as one who did not have a very high level of Latin... 

Putting cases due to influence from Greek aside, I'd say that possible counterexamples to the rule that Latin neuter plural nouns do not trigger singular verb agreement can be explained away for different reasons: for example, attraction with another nearer NP, as in the following example from Sallust, commented on in this [link][7].  

> _sed ei cariora semper omnia quam decus atque pudicitia fuit_  (Sall. _Cat._ 25,3).

Finally, apropos of this question, let me tell you an anecdote. After reading the following assertion found in this [work][8] ("Another Greek peculiarity, 'neuter plural nouns take a singular verb', is not entirely without a parallel in Latin (Livy IX, 6): _Paludamentaque detracta miserationem fecit_"), I said to myself: Eureka! Not only I found a relevant example for the question above, but I also discovered a great example for a previous question of mine (see this [link][9]). That's really killing two birds with one stone, I thought. But my happiness only lasted a couple of minutes. I checked Livy's [text][10] and, alas!, I realized that the author of the abovementioned statement quite probably misanalyzed the sentence (NB: in any case Livy's text is interesting: e.g., see the non-trivial addition of _id_ in some [editions][11]). As we say in Spanish, "¡mi gozo en un pozo!" (lit. 'my joy in a well!') or, should I say, "¡ _nuestro_ gozo en un pozo!", since this is not an example of what you're looking for either. 


  [1]: https://books.google.es/books?id=LJ2WkJOs3R4C&pg=PA146&lpg=PA146&dq=Gualtiero%20Calboli%201999%20Graecism&source=bl&ots=jPoSBuGxaW&sig=ACfU3U13JDluBg2NSMjksWsGSFb-BVMsKw&hl=ca&sa=X&ved=2ahUKEwjnta2Xv7zqAhW5DWMBHauACfAQ6AEwAHoECAoQAQ#v=onepage&q=Gualtiero%20Calboli%201999%20Graecism&f=false
  [2]: https://books.google.es/books/about/Lateinische_Syntax_und_Stilistik.html?id=1RKPZSUBNaMC&redir_esc=y
  [3]: https://en.wikipedia.org/wiki/Wilhelm_Baehrens
  [4]: https://biblio.ugent.be/publication/4145977
  [5]: https://www.cambridge.org/core/books/an-anthology-of-informal-latin-200-bcad-900/D18A6FCCA47DE1315AA57ED489037D18
  [6]: https://ore.exeter.ac.uk/repository/bitstream/handle/10871/11541/The%20creation%20of%20Latin%20teaching%20materials.pdf?sequence=2&isAllowed=y
  [7]: https://books.google.es/books?id=giQPAAAAYAAJ&pg=PA4&lpg=PA4&dq=cariora%20omnia%20decus%20atque%20pudicitia%20fuit%20Karl%20Gottlob%20Zumpt&source=bl&ots=ONt85680Ki&sig=ACfU3U0bfhiA8rL1etEbOBXRGSLAc7NsZw&hl=ca&sa=X&ved=2ahUKEwjCnsDQyrfqAhVx5eAKHRgTAx8Q6AEwAHoECAoQAQ#v=onepage&q=cariora%20omnia%20decus%20atque%20pudicitia%20fuit%20Karl%20Gottlob%20Zumpt&f=false
  [8]: https://books.google.es/books?id=1sAEAAAAQAAJ&pg=PA480&lpg=PA480&dq=paludamentaque%20detracta%20miserationem%20fecit%20neuter%20plural%20nouns&source=bl&ots=23r1Wx1sI5&sig=ACfU3U2qFJx60Idw5oSCCyZFCZNK1alesQ&hl=ca&sa=X&ved=2ahUKEwia0Jm7uLfqAhURkhQKHRLECRoQ6AEwAHoECAkQAQ#v=onepage&q=paludamentaque%20detracta%20miserationem%20fecit%20neuter%20plural%20nouns&f=false
  [9]: https://latin.stackexchange.com/questions/8839/subject-verb-agreement-when-the-subject-is-a-dominant-participle-construction
  [10]: https://www.thelatinlibrary.com/livy/liv.9.shtml
  [11]: https://books.google.es/books?id=ebE8AAAAIAAJ&pg=PA161&lpg=PA161&dq=Drakenborch%20Livy%20paludamentaque%20detracta&source=bl&ots=0zNSSOoJv3&sig=ACfU3U0vmsueUn7EuFmFH3RH-rFMVSkHQg&hl=ca&sa=X&ved=2ahUKEwjuwJ2P4bvqAhVS3IUKHbWvCk8Q6AEwAHoECAcQAQ#v=onepage&q=Drakenborch%20Livy%20paludamentaque%20detracta&f=false