I'm kind of half and half here.
If there was half of the team on the bridge, Luke was right in banning.
Win or not, killing half of the team, screwing with THEIR scores, to save your own ass, is not right at all.
Now...
If there was only the zombie there, he had no right.
...
Luke is a hardass, and for good reasons too.
When he got admin back, the server started cleaning up, because he doesn't put up with ANY bullshit...