@MojangSupport 3/3 doesn't even let you create a world and invite people. I have also tried setting up a dedicated server but he cannot join it from Android or PS4 Minecraft (both of which we ALSO paid for). This is a scheme designed to screw people out of money, right?

Sounds like actually it may just be a quick fix! You likely need to enable permissions on the child account for multiplayer and join/create clubs to "allow." Detailed steps here: bit.ly/3zjgZ6W but let us know if that's not the issue! ^AM

That's all been enabled. Was researching this for hours.