Well, I say hold on a minute. It hasn't touched the ground, standing dead? I'd say, if there's a chunk that you can cut into, not the prime stave section, but some other part of the main trunk, dig in and see what it looks like. If theres discoloration, fungus or insects, than sure don't waste your time, but....
I've heard/read about NA folks using standing dead wood. Granted it was mostly softwood, stuff that's naturally repels to decay. On the other hand I seen standing dead oak that was plenty sound stuff. At least its worth investigating for the sake of science, (and our curious minds)!
Gabe