can attorney/lawyers find out confidential things concerning a social media site?

[Kylie]

Okay my friend made a fake instagram account about a girl at school. She lies a lot and makes up a lot of rumors about everyone and so he decided to make a fake instagram exploiting the 'true' her. Things got out of hand fast the next day the girls mom calls a whole bunch of parents saying if it isn't taken down by tomorrow then everyone will know who made it because she is a lawyer/attorney and she has friends who can contact instagram and they can and will find out who made the account. The person who made the account will obviously be in a lot of trouble. But i know who he is. Because hes my friend. And i don't want him to be in trouble but he doesn't believe they can find out who it is. He says that her mom probably just said that so he would take it down... so do you guys know rather or not someone could find out who made it. I dont want him to be in trouble or his family to be sewed or whatever and im worried about him.