I received a suspicious email from "Fab - #901642 fabids@ofegrp.site" asking me to verify myself as a seller.

I received the same email and it also seemed suspicious to me. I just sent an email to Fab support asking the same question. I recommend NOT clicking on the link that appears in the email. When you hover over the link, you can see that the link it directs you to also has a suspicious address (attached screenshot)