Folks - it does require some strategy and some luck.
I just beat Tier 1 with the following crew, certainly not maxed out (have been attempting since yesterday eh, but the satisfaction of finally doing it!):
Palp (L) 6*, L78, G8 (abilities maxed)
Vader 6*, L80, G9 (abilities maxed, no zeta)
Snowtrooper, 5*!!, L61, G7 (abilities L5)
Royal Guard, 5*!!, L60, G7 (abilities L5)
Tarkin, 5*!!, L62, G7 (abilities L6)
Except for Vader and Palp this Empire squad is underwhelming compared to the recommendations for crew level for the event. I had everyone alive and at full health going into 8th stage, and only RG perished...
Keys to my victory:
Palp lead granting TM to allies who apply debuffs
Vader being able to triple shot because of that if you time his specials right
Snowtrooper granting TM (even on L5 ability) to whole team every time an ewok dies
Tarkin using basic and "Intimidation Tactics" to build up potency until the last round for his AoE
Royal Guard applying speed down, defense up and stun at key intervals
Watching Ewok turn meter like a hawk!
Some good RNG!
:)