@quid, OK, thanks, I sent the request.

I see the public profile for the older account here: mathoverflow.net/users/13049/passerby51, but I don't have access to it.

The problem with the solution in that link is that I cannot see the other account. I have only used my Goolge account to enter this site and that redirects to the newer account here. Do you see which email address is associated with that account?

Thanks. It seems so, although I cannot see the other account. Who/how should I ask this?