"We were told that it was not retained," said one of those lawyers, Bruce Barket, in an email to CNBC.
That incident occurred weeks before what authorities have said was a successful suicide attempt by the wealthy investor Epstein in the same federal lockup.
Tartaglione claims he saved the life of Epstein, a former friend of Presidents Donald Trump and Bill Clinton, during the first suicide attempt.
If the video shows Tartaglione helping Epstein, it could bolster an argument that he should not be executed.
Guards at the jail are required to conduct multiple scheduled head counts of inmates, and also to conduct rounds of the facility.
After the suicide attempt in July, Epstein was briefly placed on suicide watch and then placed on psychological watch for several days.
Video surveillance shows no one entering or leaving Epstein's cell after he went into it on the evening of Aug. 9, according to federal authorities. »