Regain Access to Amazon Brand Registry

The brand was egistered with Amazon Brand Registry using a different account and now I cannot get access to the emaill address from the person. I can still see that our brand store is still visible and accessible on AMZ US marketplace, which means a certain account still has the Brand Registry.

I have to regain access and transfer ownership to our account which I'm intending to use. But, I'm totally stuck and can't move forward. I've already opened a case in Brand Registry page and Seller Central before, but it automatically cancels after a few days. I have access to the Company info, patent info, Registration documents etc to prove ownership of the brand.