I don't see this as disruptive to the server, causing complaints or grief, or effecting the outcome of rounds in any way. 99 percent of rounds when 1 delaying enemy is left, usually some worthless kiting ranged class who will eventually die, people get bored and stand around and clan mates start attacking each other. If I was to retroactively ban for every individual I have seen do this behaviour, I would ban 3/4 of every clan's active roster.
No bans should be had here.