Lots of ways to get a girl in your hotel room in Bangkok. Just go to Soi Cowboy or any other walking street and bar fine one. Or get on the Thai Friendly app and have a freelancer come to your room. Then your wife walks in and "discovers" you in bed with her. Have your wife attack her and watch the fight!
For a safer and less dramatic idea, you and your wife can enjoy the Bangkok nightlife and start asking the thousands of working girls that are in nearly every bar and alley their price for what you want. The rougher you expect the fight to be the harder, and more expensive, finding an opponent will be.
The quickest method is probably to start asking the mamasan in each bar if any of their girls are up for what you want. They know what the different girls they manage are willing to do and can match you with the best opponent. That way you can sift through hundreds or even thousands of girls quickly.
It would be even easier if you make the 2 hour trip down to Pattaya!