I don't see what would be wrong about killing anyone who is helping you if that person is a target or objective to be assassinated/removed.
Rev wise, I like to see it as red october, fuck whatever is in charge, get rid of it, we're in charge now. This game is very similar to trouble in terrorist town for both syndicate and even rev head, and these games are all about manipulation and backstabbing. Think of this efficiency wise. You're hurt, you're getting healed by a head surgeon who happens to be a target of your revolution. Waiting until fully healed and then taking the opportunity of his proximity, and the concentration of his mind in other matters, to then spray acid in his face and take him out of action, Not only have you made sure your own life is in good hands, you just succeeded in taking out one of the main targets of a revolution. Sounds like a double whammy to me. Now sure you could get into all the psychological stuff about how no one in real life would harm someone who just saved his life, but that actually happens, and to be honest, I think that can stretch to this game as unrealistic and silly as it is, and he chose to say fuck it and kill him anyways, instead of saying hey, this guy is in the medbay in a non suspicious way, or just leaving it to someone else down the road. The guy is going to get fucked up either way in the end, and you can't start helping or defending him, you're a rev head. I'm pretty sure once you're a revhead you are INTO that cause for all glory above and beyond, no turning back.
Christ, It would even be an amazing idea to injure yourself or have a fellow rev head injure you just so you could get close to the guy in the process of the nature of his job.
Capturing for political prisoners can be neat and all I guess, but I'm pretty sure history has shown you're better off completely burying what you remove.
You can take your specific case arguments to your forum, but I'm starting a little discussion over such an event for SS13 discussion in general.