From what I know the "alt account" rule only comes when both the main account and the alt account is enrolled in the same campaign however if one user only has one account enrolled in one campaign even if its an alt then it's still allowed without any kind of violation whatsoever...
1 bitcointalk account per person(If you are found to be enrolling alts you and your alt are kicked out with no pay)
5. Enrolling alts will result in both of your accounts removed without payment.
I was also sure that in one bounty campaign member is not allowed to use his main and alt account if have any but if he is enrolled in two different bounty campaigns with his accounts then there should be no problem.
It would be great to confirm or deny if this is truly the case? Are alt accounts allowed if the main account is not involved in this same bounty campaign or alts are not allowed at all?