It does seem like they might have left it murky intentionally.
That said, it really did stick out that one of their powers was seeming compromised as soon as that stuff came into play.
As for it being "Maurauders Only..."?
It does seem like this is right in the aftermath of not only some of the team threatening him directly, but the rest of the Council essentially hanging him out to dry. Feels kinda like he is working an angle and settling scores all in one fell swoop.
Not so much "This Team Only..." as "This Is The Team He Could Do This To With The Smallest Chance Of Being Caught..."