Trouble linking Xbox (microsoft) account to stand-alone PC account

I would like to play back and forth on my PC/Xbox. This would mean I would purchase early access on Xbox separately. However, the problem is that I can't get the accounts to link. I get the message "cannot link accounts with the same login method".

If I purchase EA on the xbox, I'm assuming I won't be able to access the characters I've started on my PC account, which defeats the purpose of me purchasing the Xbox access.

I've tried:
Changing email on both accounts
Contacting support (sent a request on Nov 19)
Looking for a way to delete my XB account (no way to do this without support)

Anybody have any ideas? I would happily just let CS help me, but they've taken over a month and I've gotten two separate replies. One reply says they're looking into it. The other says there's nothing they can do (this one was sent first). So it really doesn't make sense at this point. If there is nothing that they can do, it would mean that I'd never be able to use the cross-save feature, essentially. In which case I just won't buy EA/mtx on Xbox. I'd think they'd want to find a solution since they're losing money here.