Xbox - Attempt to connect to online error code 524.

My son plays Plants Vs. Zombies: Garden Warfare 2 with no problem. He can not connect with his account (which has no age restrictions) for Battlefront II. In fact, my Origin/EA account, which I'm using now, is mine, and shows my correct age (49). Additionally, the controlling Microsoft account (also, mine) has my child set with no restrictions other than I have to approve purchases.

In other words, with our current configuration, EVERYTHING works as it should EXCEPT Star Wars: BattleFront II multiplayer, which gives us this 524 error.

This whole process is ridiculously complex and confusing, and yes, VERY disappointing for a child who got this game for Christmas.