I recently applied for this website using my @linkinpark.com email address, and was quite distressed to learn that the email address that costs me $30 a year doesn't count as a paid email. I understand that the rules say that unpaid email servers aren't welcome, but I am disappointed that decisions are not researched before hand to determine email addresses that are from free servers and emails that aren't.
The application was from firstname.lastname@example.org, if anyone feels like correcting such an awful mistake.
You seem to care enough to follow up on it. I would advise simply registering with that e-mail address again, and if any of the above who responded to you are the ones handling your join request they may remember this and approve it.