I have no idea what direct feedback the reps got during after the initial IA so the following is just my guess:
I don't think the shock of losing Staff Travel is/was the reason for halting IA after just two days...or at least it really shouldn't have been, given the warnings and what BA have done in the past. Also many seasoned staff travellers over time have come up with options for a work around (e.g; LoCo, drive, train) though I do accept a few are very exposed.
I think the much bigger issue for many might have been the imaginative way "strike day" rosters were constructed and then how pay was docked for trips that didn't get flown.
As for parallels with the rail dispute..same basic industrial relations environment, yes, but different trainset
when it comes to management attitude and customer options.