If he can't damage them then how will this work
If his mission does not include damaging anyone (example: ride in vehicle X) then the player will not be able to damage anyone.
If his mission does include damaging anyone (example: protect object X from person Y) then he will only be able to damage person Y.
If his mission includes damaging everyone (example: kill person X while not damaging anyone) then he will be able to damage not only player X but everyone since everyone is included in his mission.
What if somebody baits him
Do they know each others missions?
Because if they don't, then it won't be possible to bait someone.