Since you traded with your partner before hopefully they have your friend ID. Your best bet at this point might be reaching out to support and explaining that you wiped your data thinking it was linked to another account and now you're unable to access your stuff. A friend ran into something similar before and support was able to link their account number to their Google account so they could restore everything. IIRC support wanted to know their username and friend ID if they were able to provide it. Maybe they can do something similar for you?