You are very right about time is important. You will need to push the doctors, EC is a very hard cancer not all of them are willing to try.
I would suggest you call University of Pittsburg as well, and Sloan Memorial NY.
My husband was also non-operable. Just my opinion but once it spreads seems like it becomes more specialized. You will hear, that it is EC cancer cells so they don't switch to bone chemo drugs, but when you make an appointment ask to see both specialist one for EC and one for bone.
If your Dad wants more treatment you have to get very very tough with doctors. "He wants to continue, you are obligated to find him treatment". "If you wont treat where and who shall we go to."
Several groups have transportation services, if you get stuck holler. I'm the PA rep to help get people to other survivors, I'll email the MD rep now.
Where does he live ?
The road is a hard one, hang in there