He's a good man and he's a stormtrooper have a small battle in her mind, unable to apply the past tense. She trusts Poe, insomuch as Cassian trusts Poe and that can tide her over until her own foundations of trust are stabilized but, even without all her memories, it is hard to turn off thirteen years of conditioning that stormtroopers equal bad.

Even with Bodhi and her father

Her eyes dart to Cassian briefly, somber mouth pursed. "Alright." Finn is a good man, Poe decreed it and Jyn is willing to go with it for now. Maybe solely because he's not here.