Before I respond, consider this: The mafia had already determined for themselves that Rich was the real detective. They also they knew well in advance of nightfall that he was their next hit.
As a side note, I think it's worthwhile for us to answer that question too.... "how could they have been sure it was Rich instead of Pir who was the real PR?"
That's actually quite obvious, now.
The mafia knew Piranha was lying the whole time --> because Piranha named an innocent as scum.
Pir's claim was wrong (they knew that); Rich's claim was right (they knew that too). The mafia knows who their teammates are.
The mafia, therefore, wasted NO time whatsoever trying to decide between Pir and Rich as the real detective. They knew it immediately, as it was happening.
So throughout the whole second day, all 5 of the mafia team - including Zaffy - pretended to be confused and unsure which role claim was the real deal.
Now then, let's look again at your questions and other points made in the above post.
1. Rich was no threat to the scum. This is not true. The opposite is true, in fact. Rich was the biggest threat the scum team were up against because he was the (only) one who could investigate them. Rich is also a shrewd player, as shown by his first investigation pick... he had already nailed Zaffy as mafia.
Rich didn't tell everyone else about that investigation result right away, of course. He waited until after Pir interfered with the game with Pir's false role claim before coming out himself, but Rich knew already from night #1 what role Zaffy had.
2. If JB was going to turn innocent why not let Rich live? No use speculating on this at all, folks. We already have that answer.
(Hint: See Item 1.)
The mafia already knew Rich's first investigation was accurate. They could not afford the risk of allowing Rich to live long enough to investigate anyone else.
The mafia could see clearly that the town didn't know yet which RC to believe. But Rich was the real detective and no matter who he investigated next.... if Rich was still alive, he would report those results to us immediately.
The subject of his second invest (JB) was immaterial. Whether Rich found scum and confirmed that for us or whether Rich found an innocent and confirmed THAT for us.... this knowledge would help the town and hurt the mafia.
It was just a matter of time (and very little time at that) before the town found out Rich was telling the truth.
For the mafia's best interest, Rich had to die as soon as they could kill him.
3. We wouldn't have a known target in Zaffy/still wouldn't trust Rich. I disagree. I believed Rich before nightfall came and said so. Apparently, so did many others. That's why very few people voted to lynch Rich (take a look; only 2 votes there).
Add to that, after the death of either Haydn or Piranha and having their role revealed.. Rich's claim would have been further reinforced, if not all-but-confirmed in the minds of many townies who were still unsure. This is a process of elimination if nothing else.
Also, whoever the second investigation result revealed as innocent or evil... that person would also know Rich was accurate. If mafia... they would fall under intense scrutiny from everyone (along with Zaffy). If townie... they would side with Rich to help the town go after other mafia members. Zaffy, meanwhile, was already under enormous suspicion and that would only have increased.
4. More would have thought him scum had he not been the hit. Disagree with this too... in this case. Most of that was covered in Item 3.
With that said, I see you (and some others) are concerned about JB's role. Don't be.
Going back to the point I made above... the mafia knew with full certainty that Rich was telling the truth (Zaffy) and Piranha was lying (Haydn).
With that knowledge already... no one on the mafia team would have voted against Rich on Day #2. They all already knew he was going to die next because they intended to hit him. No question there.
Once Rich was revealed innocent and as detective, no one on the mafia team would want to be seen as trying to get Rich lynched. The mafia's best interest in that case would be to distance themselves from their own mafia hit. I believe the only votes cast against Rich were made by townies who (at the time) truly believed Rich was evil and lying to us.
