What does the applicable state law say? Is there a a "time line" where your anonymous "friend" can prove their "worth" to regain their rights?
And, yes, if he is in possession of firearms illegally you are under an obligation to report that fact to the authorities. Failure to do so could make you an accessory if he commits a related felony. Not every state makes it a crime not to report a crime, but it is still every citizen’s responsibility to do so. If you know a felon has possession of a firearm, you should inform the police.
You are aware that it was dems who introduced (and continue to introduce) gun control laws limiting firearm ownership when years ago they were not breaking the law?
And no, I would not even consider ruining my friend's life when he has proven he is a responsible and productive citizen after all these years.
Again, answer my question.