Hi
I'm sorry, a lot of this thread I cannot follow due to not knowing the email addresses or forums
I would like to though, remind everyone that until recent years, forum registration did not require separate confirmation (some may still not), webmail access would not show on pc if hacked, and yahoo (and a lot of other db, e.g. Talktalk avast etc) were compromised and email addresses taken. There will be a lot unpublished. Also, any domains registered were and/or still show owners email address. Even if the owner changed to hide details, time web still show these details and once part of a domain is known, it is easy to tie most forum users with a domain part, first name etc, so algorithms are scripted to generate email addresses.
This is true of nameservers/dns, where a domain is hosted, rdns of the host ip to reveal details of other websites hosted, yielding more to speculate for gathering.
We use honeypots, to help the Internet community further and those who use honeypots to stop access to the websites/servers
There is a lot more but time is short and I have my grandchildren stopping with us for a few weeks
I hope that helps rather then complicate issues
Many thanks
John