Can a parent authorize Discord app for child on iPhone?

I just created a family share on my new iPhone 15 Pro Max(I’m just converting from a droid to an iPhone). My son has utilized the discord app on his iPhone, but he had an incorrect date of birth that was associated with his Apple ID, because neither parent had an Apple product at the time that my son received his. (and off memory in order to set up the phone or get it ID or utilize some subscriptions. He needed to have a credit card on file.)

Now that I am creating the family share portion on my new phone , in order to utilize family share options ,I had to correct his date of birth that is associated with his Apple ID. (he is 14)

Unfortunately, now it gives him a restriction and it says he cannot open his discord app. It won’t let him open it isn’t located anywhere on his phone.

How can I, as a parent, authorize he has the app, even though he is listed with his Apple ID as under 17? basically, I had no idea it would take away the discord app, and I am OK with him having it but discord and or Apple isn’t. What is the workaround as a parent?

[Re-Titled by Moderator]