CMS, I'm sorry you are having to deal with this and I'm afraid I can't answer most of your questions but I will be curious to see what MD Anderson says compared to DF.
Since you've had two recurrences, even though they were all Stage I when caught, it's obvious you have an aggressive form of cancer that isn't being caught entirely by local surgery. DF has recommended a correspondingly aggressive treatment plan (which they did for me too by the way, I wsa Stage II, though I wasn't dealing with a recurrence). The way I look at it, you want to be aggressive in your response, especially when it's clear the cancer is aggressive.
It sounds like you have not had any kind of neck dissection? I suspect that is something any place will recommend, since it's possible there is cancer in your nodes that won't be detected by CT scans.
Anyway, good luck with the trip to MD Anderson. Any insurance company should cover the costs of a second opinion about this and the cost of tests they will want to do. If you go there for treatment, you probably will need to find your own way of covering the costs of housing though. I'm sure MD Anderson can help you find something reasonable if you end up making that choice.
I'm sure lots of other people here will be along who can answer some of your other questions.
Nelie