I have a dukes dog proof, even went to the trouble to modify it to be double throw. Tried it for 2 years and never caught anything in it. My go to is a #2 coil spring trap but you have to check it daily. A coon will eat their leg off.
If they are stealing the bait you need a small bait cage in the trap. Lure them in with just a few pieces but 99% of the bait is in that cage so they can only smell it and try to fight around to get it.
Oh now, I have a soft spot for coons, lmao. I have no issue taking any wildlife over my livestock.