I Just Learned Something And I Hate It
This achievement only progresses when you grab someone from your traps. There is literally NO indication that you are suppose to do this. Especially when the Bloodpoint score is called "Grab Trapped Survivor" and not "Catch Trapped Survivor".
Hitting people with a basic attack while they are in a trap does not progress it. People getting caught by your traps and escaping does not progress it either.
Please BHVR, word your achievements better or make the conditions required reflect what the achievement says to do.

Comments
Always been this way.
The text is poorly worded, however it does say to "catch" a Survivor in your Bear Traps -- which can be interpreted to grab them out of it.
I'll be honest when I think of catching someone in a trap I literally just think of them stepping in it. Not even me walking over to them and hitting/grabbing them.
Maybe I'm just dumb.
I can see that, but like I guess you just didn't CATCH them, y'know? Like you escaped from the bear trap, you need to catch em good and well, lol
You're not dumb, that's how I thought it was too. Catch a survivor in a bear trap does not at all sound like grabbing them out of it. I thought it was exactly what it sounded like, catching someone in a bear trap. It does need to be worded better.
The wording is terrible especially because the Trapper daily says "catch 3 survivors in bear traps" and for the daily the survivor just needs to step in it, not you have to grab them out of the trap like the trophy. They really should update the wording of the achievement to remove the confusion.
THIS^^