I think context should matter.
If you accept a quest to hunt down robbers and you lose companions in that quest, villagers shouldn't refuse to join up for other types of missions because you're an untrustworthy murderer, unless none of them survived (survivors ought to be implicitly assumed to be able to confirm of your story through rumors, even if you don't have them with you at the time you visit that village again).
If, however, you hired someone for a hunting trip or to help out on your homestead, you should have to have a lot of explaining to do to get anyone to risk it with you again (if a robber band attacked you in your homestead and you can prove that, the death of your hired help might be considered to be on the robbers, not you, but if you took your hired hand to hunt robbers, that's a different matter entirely). It would probably be difficult to implement the explanation bit for anything but the robber quest, though.