Adjudicating combat effects

[TheAmishStig]

Over in Munchkin 101 there have been a few threads now about combining auto-kills and combat cancellation. I thought I understood what was going on but was proven wrong in the most recent one (found here); Andrew mentioned we're going well beyond 101-level concepts, to please create a thread here, so...yeah. Thread!

As an MIB figuring this stuff out once and for all is important to discharging my/our duties, so hopefully this proves helpful to demo agents and players alike.

In the linked thread, the following scenarios were presented:

Scenario A:
- Action: Combatant Player auto-kills the only monster in combat
- Action: Non-combatant Player attempts to play Friendship Potion (or other combat cancel card) to deprive the player of their winnings (levels/treasure).
- Question: Does Combatant Player get the rewards from the killed monster?
- Ruling: Since the specific combat canceler targets a monster, and there were no monsters, therefore the card could not be played. If no other actions are taken, combat is over, Combatant Player wins, and gets the listed rewards.[2]

Scenario B:
- Action: Combatant Player auto-kills the only monster in combat
- Action: Non-Combatant Player uses Wandering Monster to continue combat.
- Action: Non-Combatant Player plays Friendship Potion (or another combat-cancel card)
- Question: Since the first monster was killed prior to the combat being canceled, does Combatant Player get its reward?

My understanding in scenario B was that it depends on whether it's a combat cancel card (as if combat never happened, such as Friendship Potion) [1][2] or a combat replacement card (changes the outcome, such as Out to Lunch)[2], since combat is all or nothing...either the combating players win (by comparing combat strength, even if auto-kill/out to lunch reduces the monsters' combat strength to 0) and get rewards, or they don't (either by Running Away or by a card that negates the combat) and get nothing...but the latest ruling leaves me more confused than anything[3], since it negates the combat but still gives rewards for the auto-kill.

I...officially don't get it, there's got to be something I'm missing. When making calls like these in a demo or tournament situation where we don't have the forum handy [or time to wait for a reply], what should we be looking for when ruling whether or not the player gets to keep their rewards?