It is legal in New york to record conversations so long as one of the participants knows that a recording is being made.
The video recordings might well strike a Judge as a bit heavyhanded and can, in that sense, boomerang.
At any rate, my guess is that his admission on tape may be a tad perfunctory and thus may not even be expedient to use in court.
Good luck to you.
As always, do not construe posts as legal advice but as "attorney advertising" and you should always consult with a lawyer on any legal matter.
It appears that you want to change your custody agreement because of a change in circumstances and that you are willing to take this issue to court. Consult with counsel before you take any actions which he might argue as "parental alienation".
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