There is no way you can hang a 500# MC on only a receiver hitch. Even if you have a hitch rated for 500# direct load, you are going to have a long draw bar to get a wheel rail far enough out from the rear of the trailer. That is a long lever, and that cantilevered load is going to far exceed the capacity of any receiver.
I don't know what length draw bar they use to rate these hitches. There is a lot left to the imagination since we don't have any of their design documents. But I can assure you it is not based on a 2' long draw bar.
This whole idea is just silly.
