There was a somewhat appropriate reaction - someone pointed out that you couldn't save people past a certain point. But the breachers and the medicae are fairly understanding of a motive like "We might be able to save a life", even if they think it's pointless. Sure, there's going to be some questions about the technology in question and his general actions, but a magos having unique knowledge that upends conventional thinking is basically a trope at this point even in the lore.
I am not blind to the fact that people in-universe aren't going to easily accept the crazy tech the MC is building/using, but the fundamental position of being a tech-priest is that you get latitude from just about anyone who isn't familiar enough with the Mechanicus. Even then, magi are too diverse a group to instantly identify someone as atypical on the basis of action alone.
