Thrawn 7* possible

Your gear levels are good and omegas are good, and Ezra’s speed is good. So it looks like you’re going to be heavily relying on Ezra for the event. With favorable RNG, that’s possible. But if Thrawn and co. target Ezra, you’re toast. So you may have to try several times before you can get it, and you might not get it at all.
I’d really focus on mod farming during the event. If you can get Hera and Zeb faster, that will help you a lot and make the event a lot less dependent on chance. Get Hera and Zeb to 180+ speed and you’ll get it no problem.
And to your question, if you can get 7* Thrawn, you can get 7* Palpatine without difficulty.

It is possible. I did it with not all abilities at Omega and no Zetas. No speed mods so I used very good health mods. Ezra was Gear 10, Chopper Gear 9, and Hera/Kanan/Zeb at Gear 8. Check out my Strategy on “Best strategy for thrawn” on the previous page.