An accidental teamkill and undeserved insult to your full blown intentional revenge teamkill?
It's clear you over reacted.
His poll was in response to yours, not a ragepoll, more of a revengepoll neither passed, but then you made things worse for yourself by teamkilling him, giving him the perfect opportunity to get you banned.
Your ban stands for the teamkilling but an accidental teamkill, a single one off comment and a response poll, I'm not doing anything about that. If it was harrassment, it would be a different story, but it's not.