Hey just saw your turt issue and decided to show up

What your seeing is normal turtle behavior because you have 2 males, and its actually on the lower scale comparing with Ive seen male sliders do and thouse are closelly related to painteds. The treatment your doing is correct, however besides the obvious wound I think there may be one or more abcess in the interior of it. What I sugest and since the wound is open is use that in your advantage and in a gentle kind of way try to press the wound toards its opening, if there is dead tissue inside of it you will feal something hard or skishy. Dont worry about hurting your turtle, turtles have increadbly tough skin (giving them stinches is a nigthmare) and the wound is on a fold of skin, so the wind pipe and the other throat structures are far. Use comon sence in the amount of preassure to apply, I cant tell you how much, first have a good feal of the wound and then make your desision. I think there may be something in it, Ive seen big pus chunks coming out of wounds like that. If something comes out wash the wound on running water untill no more bad stuff comes out and because its a deep wound dont apply betadine directy, use oxigen peroxide insted first and then water again and keep it very clean. Dont worry, turts can easily come out of situations like that.