Well, the closer the sat's longitude to yours, the higher up in the sky it is. For you, that makes quite a difference between Bell and Shaw (22 degrees for 91 and 32 degrees for 107).
I understand that you were sighting for bell's azimuth - and came up about 125' short by rough sextant - but shaw direct will be much higher than bell, if the mountain is comparable in height along the azimuth required. Either way, when I calculate based on your numbers, you clear the mountain with both bell and shaw (albeit barely with Bell):
Tan(radians(22.5)) = 0.414 Bell @91
Tan(radians(31.3)) = 0.608 Shaw @ 107
You are 2000 meters away, and already 900meters high:
900 + (0.414 * 2000) =1730 meters (Bell)
900 + (0.608 * 2000) = 2116 meters (Shaw)
Mountain is about 1524 meters high - should give you 200 meters room on Bell (not much) and about 600 meters on Shaw (enough to play with?).
Good luck, let us know how it turns out.