@monkry Yeah, I think Yun has something up his sleeves, and he intentionally tripped himself to fire the flare gun. It looks like he knew some shit is going on with how he acts.
Probably has his doubts when that friend of him died without any traces (killed by the team, maybe?).
Edit : not to mention he "tripped" after arriving at the entrance of the dungeon while standing still, which is...yeah.