I looked online and apparently this bug should be solved by using G.CD_Quest = 1 on the console but that didn't seem to work.
I picked the flesh ball and the nosferatu photo before triggering the quest without realising they were tied to the quest.
The order you get the items in is not important, also you don't get the posters in the mail box, Gary will have them stuck to your walls instead :)!
Also the posters will be absent every second time (literally) you enter your haven.
Also they will be present in all havens simultaneously...
I never heard that before...
If you aquire a new haven after the SM one, the posters will vanish there!
They definitely didn't vanish there at least once [in the past 2,5 years], but I don't remember their current behavior (too bad my recent saves are already deleted). Maybe it was recently fixed?
It does seem to be a thing, but never bothers me so I never question it.
That info is outdated, the right command is G.CD = 1!