Sorry to hear this. I think you burnt yourself with the first freelance attempt, perhaps would have been different if you'd tried the Muay Thai route first time around. I don't think that being a landlord of a property and gaining income that way counts as freelance work (in their eyes). But don't dispair, try from another country with the Muay Thai attempt, Cambodia, Vietnam etc. You can do it!
I don't really understand why people need agents to help with DTV. Can you tell me why you can't do it by yourself? I'm not judging anyone here by the way, I'm just curious