The last time I looked it was against the TOS to countermand another admins command, unless of course it's ZERO or another high ranking IBIS member. That infraction is for Z or other IBIS to deal with but it should be dealt with before it becomes common practice going unrecognized.

W/E but why not just unmute him officially by the admin (Taz) that muted him and put him on probation for a week or so and see how it pans out.