I was able to finish the normal one. I used
Tarkin g8 70 lvl 6*
Vader g8 75 lvl 6*
Tfp g7 68 lvl 5*
Ig86 g7 76 lvl 6*
Rg g8 78 lvl 5*
Tarkin was the leader and my tfp's speed was over 200 with Tarkin's leader ability. Back then i was lvl 78-79. Also, my empire and droids were not so good. However, I managed to complete without having Palpatine. I think you can complete. It is important not to get any damage from the ewoks which has low health but huge DMG. Use Tfp, Tarkin, not vader to smash them immediately. Keep Vader's ability for the others. I hope this will help.