That’s pretty powerful research pointing at them, but before I would say the research is conclusive, one would have to know more about the email account.
Such as, is it a webmaster@ “anything”? (info@, sales@, support@, tech@ etc…..)
Is the email account with a major or minor ISP?
Is the email account used as a parent email for a web hosting account?
Is it possible the administrator of the domain where the email account came from could be selling the accounts? (whether they say they are or not)
I am not saying you are wrong, but just cautioning not to jump to conclusions too soon….if you are correct then I totally agree this is wrong.
Rick
Universal4