Oh sorry, I didn't know that giving a ring to a girl had such an intention, don't mind me as I just put it on your ring finger, it means nothing. The level of dense on this guy...
And because they know he's a master "trapper" they'll assume he can only lay traps, which honestly if I was them I would be paranoid as hell of being surrounded by traps and I would've at least gotten one guy to handle the guy that can manipulate the battlefield.
But no, we're dealing with idiots all around, so it'll get resolved through typical swordsmanship and straightforward mastery disguised as "trap combination". And maybe, miraculously, one guy will try to escape and will accidentally step on a proper trap, just to provide a reminder that the MC's core power is intended to be about setting traps.