First off, you guys are idiots for having access to the eval command on your servers. Secondly, Truce has always been known as an abusive script kiddie and it's your fault for not being careful about that.
You pretty much only have yourself to blame - once Truce slips up enough he'll get his key revoked like all the dumbasses before him.
I shouldn't have to handicap everyone else because I suspect somebody will abuse it. Most of my clan members are close friends who I trust very much.
Just because I gave him the opportunity to do something harmful, it's new to everyone for him to abuse it. He usually would make helpful little scripts that benefitted the builders or whoever.
Regardless of the fact I gave him the opportunity, it's still a really richard move to pull some stuff like this and not admit to it.