Would Pilot Chewie's ability cancel the R2 (crew) crit?

Just curious as I am relatively new to the game (7 casual matches) and I am still checking out card synergies and fantasy list building. Still working on building my collection.

No. You're flipping a card, not being dealt one.

Same goes for Saboteur and Rexlar Brath. Chewie has no effect on them. There's is a distinct difference between "dealing" a damage card and having one "flipped". Chewie only works on cards when they're dealt.