Wheel mount may not work for the OP as he has a class c and may not have a spare on the back.
We carry three bikes with us. I can not bring myself to spend the money on anything like Thule or Yakima. And I used to mountain bike race. We have a cheaper one that we got at Kmart. It has a bolt that keeps the rack secured into the receiver. You can do a locking hitch pin if you want. As far as security goes, we used a bike lock cable. There's no true security. Anyone that knows what they are doing, can steal a bike no matter what security feature you use. It's all just a deterrence. We have cannondales and never have a problem. We leave bike rack on the back all the time. The arms fold down when no bikes are on it. I watch the bikes via the rear camera and they do not bounce around at all. Nothing wrong with spending more money on a rack. Just not our preference in my experience with them.