This is the toughest team I've ever gone up against in Arena:
Rex(L), DN, Chirrut, Baze, GK
The closest I was able to come to beating it was using:
Maul(L), EP, Boba, DN and STHan where an early match execute on Chirrut left him with a sliver of health and it came down to Maul vs Chirrut and DN. With all of the cleaners, I would have to land Daze and then either Stun or Ability block Rex, Chirrut and GK to get the advantage needed to win the match. For each of my attempts, Daze failed to land on at least 1 of those 3, resulting in the cleanse.
B2 would normally be a good option against double taunt, but that still depends on landing Daze + Stun/AB first or the AoE will feed too much TM. Also, for Boba to be of any use against Chirrut it's usually counter productive to dispel his HoTs.