No.
NOT OK: Using a bug to gain undeserved benefits
If the player you QML dies, they can't press M and escape being kicked from the server. QMLing people in combat in general is maliciously exploiting the function, and is not the way it was intended to be used. Using QML on actively fighting players is against the rules, even if it's not explicitly listed as such.
Another player has been
banned permanently for the same activity. You had the lack of awareness to do this to me, an admin.
Never do it again. Your ban will end tomorrow night at around 9pm Central time.