RE: How do you keep a tent warm at 11,000 ft ?
We camp above 10k and use wood stoves in all 3 tents.
But we bring oak and mesquite from home as we have a drive up camp.
In the end......everyone has their opinion of what you should/could do and whether you should/could worry about being warm in your tent. My opinion, only takes a little bit more effort to go first class. If you are staying for a week or so, nothing will sap your will to live like being miserable and only you know what that is.
Well made and well designed wood stoves will work fine for your situation, just need the proper fuel. IF it is an option, I would bring some along. We burn our seasoned wood in the stoves and use the fall downs for the campfire.