You should be able to get a refund if your mid way through treatment. It's BS if you can't and I don't see a reasonable doctor saying no, it's your teeth after all. Be stern and aggressive if it comes to the point you need to change orthos.
As far the decompensation pre-surgery, have you found a surgeon? Dr Triaca? If not find a doc that has a surgical plan your comfortable with and he should then send your ortho a orthodontic plan or at least talk to him about it. It all starts with the surgeon and the ortho is secondary, following his or her lead.
Again, hard to even make assessment but I think you could get away with just upper surgery to fix the cant and advance your upper jaw for a proper overjet/overbite. Idk if your mandible is that deficient or a genio/implant could do the trick, especially if your bite is perfect with just upper jaw surgery.
And a mandibular plane/occlusal plane being steep is not abnormal by itself although it correlates strongly with LFS for example and other vertical deformities. Remember, single jaw surgery is so much easier than double jaw surgery and as long as you can get a stable, class I bite with just a lefort then I'd do that even if your mandible is potentially a little deficient.
I need to get a feel for the current situation before even considering a refund.
My surgeon will be Dr Triaca simply because he has good experience with Chin Wings and his results are solid.
You should be able to see my occlusal plane better in the CT scan I posted below. Based off my own casual observations it seems less steep than most.
The main question with upper jaw surgery is exactly as notrain has stated: the movements will be tiny, zero aesthetic improvement. So is the operation worth it for what it will achieve? Namely, "perfect" bite and fixing canting. Of course, there are then the issues of nose widening to consider.