I don't see why "Cult + Necromancer" isn't a possibility. The entire Necromancer/Ghoul issue is totally irrelevant to the nature of the main scum team, yet you seem to be insistent that it matters.
It only matters insofar as what we should be focusing on. CULT+SK is a possibility, obviously. The reason it matters is
if there's a cult then focusing on serial killers is absurd. Look, let me spell it out even more logically.
Possible Premises
A: There was no kill last night
B: There is a cult
C: There is a serial killer
D: Scum were prevented from killing
E: We should focus on killing the cult
F: A body is missing
G: There is a scum priest
H: It's OK to focus on killing SKs
Axioms:
A
IF A THEN (B OR (Not-B AND D)
F
If F THEN (C OR (Not-C AND G))
IF B THEN E
IF (Not-B AND C) THEN H
IF E then Not-H
Thus:
(Not-H AND not-D) OR (Not-B AND D)
C OR (Not-C AND G)
That's all we know. However, ZU is claiming on top of all that, without any reasoning, that:
C AND Not B
Which allows him to get to H. But there's no reason to believe in Not B over B. And if B then Not-H. Now I've laid out our disagreement axiomatically, now do you understand where I'm coming from? I'm saying that the possible existence of a serial killer doesn't mean we should focus on serial killers AND if you believe that there is a serial killer AND the we should focus on killing serial killers, then you're committed to believing in a very specific scum set-up, and there's no reason for believing in that very specific set-up. Namely, ZU is committed to:
A
Not-B
C
D
Not-E
F
G OR not-G
H
When really the evidence only supports:
A
B or Not-B
C or Not-C
D or Not-D
E or Not-E
F*
G or Not-G
H or not-H
*if we believe ZU
Now do you see how arbitrarily specific ZU is being?
I'm committed to the further view that so long as there's a possibility of a cult, we should focus on killing the possible cult (I'd have to start getting into modal logic to express this with letters though).