I really hate to come on here and be negative, there is enough negativity on this site already, BUT this is a problem that I have ran into many times in Missouri. The thought of paying a trapper is often scoffed at, and I have had noses turned up at me when I mention it. Why is this? If you have a backed up sewage pipe would you expect the plumber to come in and fix your problem for free? When your car breaks down does the mechanic repair it free of charge? Why is the service of trapping problem critters any less than any other service? Now it's said this guy is filthy rich, but yet no mention of paying for removal?
One of the best things I was ever told, by a great trapper, was this "Do not use your time and money to fix their problem" That's good advice not only in trapping, but life in general. Even if he gets backhoe going, he's gonna be tearing out those damns every other week. Spending his time and money to prolong his agony.
I hope he gets his issue fixed, but refusal to pay can complicate things and make them harder than they need to be. #1 he probably won't get an experienced trapper to do it, and then problem #2, now there's potential for joe blow down the street to be educating these beavers and making the job that much harder and more expensive when he does decide to do it right and pay an experienced trapper. As they say, money talks, bull spit walks.
Nothing negative here that I can see. Truth is always a positive.