I'm not sure.
It's been a while since I read Knight Errant, but I think I remember Kerra doing pretty well against Arkadia and Calician. A rusty Kanan was giving the Inquisitor trouble and a recently tortured Kanan that was no longer rusty out-dueled the Inquisitor.
I could kind of see the Inquisitor winning for some reason, but I'm not sure why.
If Kerra for some reason cannot win toe-to-toe, I feel like she could still outsmart him or find a way to escape from the fight.