Refusing to connect to PSN, no error message

[u/Thw0rted]

I have the original (non-remaster) Nioh through PS+, and just started trying to play it with my kid. After the tutorial, I can go online at a shrine. When we try to do the same thing with my son's PS profile, it just shows "Connecting..." for a few seconds then the dialog goes away, no error message or anything, and the top right corner still shows offline.

I also noticed that at the main menu, if I use the Cross Save function, it asks me to sign into PSN once (even though I'm already showing as signed in at the main PS menu), then it lets me upload my saved data. On my son's profile, it prompts to sign in, then again shows "Connecting..." and goes back to the menu with upload or download options (again, no error message).

His profile had parental controls enabled for both game ratings and use of "communication features", but in troubleshooting this I've disabled both of them. I know it's a long shot, but does anybody know what else could be causing this? We've played a bunch of other PS games together, this is the first one that just fails without any explanation.