It's not only plagiarism but also more than that, buying an account. The second violation is against another forum rule and it is discouraged by community too.
Reason of the ban is plagiarism but by breaking another rule, there is almost no second chance for secondary owner of this account.
Nah, it's not a violation, technically the forum allow that.
18. Having multiple accounts and account sales are allowed, but account sales are discouraged.
Who cares with the community, they can't ban any user. If the moderators or administrators choose to unban the @OP, but all the community choose not to, the user will be unbanned.
But, he might receive a negative feedback, but in this case it's about ban appeal not negative feedback appeal.