Right, re: Poisoner claiming. Think about it.
Scum had the plan of "we'll have our Goon claim #1 in the draft and Poisoner, which he can argue was to block it from town and if he fails to convince people, well at least we didn't lynch our poisoner".
Why would they want iguana to claim D1 exactly ? I'm truly curious why you think that is faust ? The direct result of that claim was that we lynched iguana on D3. Now granted, that does mean we didn't lynch the poisoner on D3 which, if there had been no claiming at all, we would have had a chance to... but based on what ? We would have nothing more to go on than we ended up having, since our (well, you know) investigative powers didn't go for iguana anyway.
So having the poisoner claim on D1 meant we gave up a tiny chance of lynching the poisoner on D3 in exchange for the certainty of a scum lynch. Poisoner is integral to scum's gameplan, true, but I don't think that's such a good deal for scum that your suspicion of me in the face of what would be very improbably Mason fakeclaim is warranted.