With Straining and Gambits, it's definitely possible to get the bear to whiff a Stand Firm roll, but their resistance to Stress means you have to do this for several rounds. Kudos to your player!
since the player was approaching it solo, and the bear's stress resistance was based off of the party, i ruled it was only one. (despite them having a party, but i let them not join the combat because player was being a reckless bear fighter)
Completely reasonable! Bears are still super tough even without the resistance, and honestly a bear might drop its guard a little at a fisher trying to 1 v 1 it.
