Cannot link EA account to PSN

I don't know where else to turn... 

I created a PSN account for my son (I put his DOB in as 1/1/2000 but still under my family PSN account). I figured that idea of him being 24 with an account controlled by me would be the best of all worlds.... I appear to be wrong. Preordered FC 25 Ultimate additional. I cannot get an EA account linked to his PSN. I have created 3 new EA accounts and tried linking his old EA account. Only 1 of those 4 are "Child" EA accounts. I keep getting the same "ineligible to link accounts" error. I know the steps for linking. I have done it on my own account and it worked. 

The preorder bonus of 4600 FC points is pointless unless he can play online...I have tried EA and Sony support. Guess what? They blame each other! WHAT THE HECK DO I DO?

Even if I could redeem those FC points on my own PSN account, I would take that at this point. I don't think I can though. I just want his 24 year old PSN account to be able to play online! Why the heck  can't i link an EA account