I looked into how Caesar uses past participles and est.
His style is considered good and he does not aim for anything particularly convoluted or poetic, so I think he is a good choice for this question.
I searched for all examples of -tus close to est in a corpus, and found the following:
- There are many examples of a past participle and an est (although there are false positives as well), so you can draw some conclusions.
- The participle and est are almost always next to each other. Both orders appear.
- There are cases where two participles go with one est, but that is not a split in the sense of the question.
- The only split examples I found were:
- est certior factus, where certior factus is a solid block on its own that perhaps should not be split by est.
- finis est pugnandi factus, which is a genuine split like you described.
- ad eum est honorem evocatus
- He never seemed to have more than one word in between, so the block was still fairly well together.
I only studied masculines, as I thought they would be quite frequent and might be similar enough to others.
I doubt that feminines or neuters would behave very differently, but I did not check.
I also only looked at singular participles ending in -tus so as to reduce false positives but to get a substantial number of hits in one search.
A more thorough study would benefit from an annotated corpus where you could search for past participles.
The list of examples from Caesar includes both deponent verbs (semantically active participles) and transitive verbs (semantically passive participles).
The literal question only concerns a specific deponent verb (nasci > natus sum), but I think the same guidelines are applicable to all kinds of situations with est and a perfect participle.
There is not as much data on the specific verb, so I find it better to look broader.
The conclusion from this quick check is:
Splitting is rare but can be done.
Caesar does it maybe in one of twenty cases.
Bear in mind that splitting can make the text much harder to parse, so communication is often most efficient if you keep the pieces together or only split by one or two words.