Kathleen:
If you already have help coming in, home hospice, that should be plenty. I know for sure I would want to spend my final days in my own home with home hospice and my primary cargivers at hand. If I were you, I would accept any help your siblings want to offer, but just tune them out when they push to move your mom to a hospice house.
The key thing, as you said, is that you are doing what your dad wants.
Don M