Clarification about instant kill situations

[Mathgeni]

I searched the forums looking for this but nothing seemed to immediately address the following question. (I believe my group has played the situation wrong based on the few things I have seen related to my question)

If someone has some ability or card that grants an automatic kill and another monster is in combat which they cannot kill, is the level(s) still gained for the monster that was instantly killed?

[Andrew Hackard]

Only if they can kill all remaining monsters. If they have to Run Away, they have to forgo all their rewards, including levels.

(Note that there are some very weird edge cases where this ruling may not apply. Please accept this general ruling with the understanding that there may be a couple of 101-unfriendly asterisks I don't want to try to unpack right now.)