DH (gets motion sick on Star Tours, Soarin', won't even look at a teacup), did awesome and in fact TSM is his favorite ride from our trip.
If you don't want to risk it I think if you talk to the CM they should be able to allow her to go through the queue and then simply cross through the ride vehicle (since it is locked and stationary during loading) and exit that way. Or there could be another emergency exit on the queue side of the attraction.