I believe MQ2Melee is set to not attack invalid targets, but that would be knowledge someone else would have.
I'm guessing your wanting to do this while waiting for pulls/spawns?
I believe EQBC still works when you /mqp on (if not, the rest here will be moot).
You could, using holys/downs or events, have one toon tell another to basically
when no mobs in camp/not in combat
1) Target pet
2) /stick on to pet
3) /mqp on
4) /attack on
Then when mobs in camp/in combat
1) /attack off
1) /mqp off
2) /stick off
just ideas....