Sorry to basically reply to myself.
I just tried out my own "standard" Padme team: Padme R5, Ahsoka R6, JKA R7, General Kenobi R8, C3P0 R5
I won first attempt on Tier 10. Again, I reckon I might have more relic levels on the rest of the team than you do, but it is actually quite possible to win with Padme, just took me some time.
Be sure to use the event special on your toons to get rid of the damage and speed reduction. Go for Bo-Katan first, as her unique grant the entire team protection regen, which is super annoying when paired with the Mando GC modifier. It will likely take you some time to punch through her, but once she is down, rest goes down more easily. I went for Maul after Bo-Katan, but not sure if that's optimal or if it even matters who you target after Bo.