ITW was also kept in the alternative setlist since... summer 2006 or something like that, so we knew about the name, just had no idea about the music.
Prostitute was exactly opposite - we had heard the piano intro many times, but had no idea it comes from that actual song. to be honest, the intro was just the intro, so we couldn't know. at least we know the song might have already been complete (-ish) by that time, because Buckethead was all over it. + we knew the title since July 1999 (Spin magazine interview)

definitely. actually there are 2 strong variants of what happened - remember most of the tracklist leaked before and/or has been played live for years.
1) they had many recorded songs ready, but were pissed off by the leaks, so they put the tracklist together to intentionally contain maximum of the leaks, with really only a few unknown songs (do you remember which songs were totally unknown by the time the album was actually released? I'll tell you: Scraped. and that's it. then, TIL and Sorry were known by name but not by the music nor lyrics. yeah, a few of the tracks were leaked or officially released quite shortly before the album release: Shackler, ITW, Prostitute. that's still less than 50% of the songs).
2) they actually only had a handful of songs at least half-complete and the whole "saga" and "legend" and "mystery" were just fake and ther was nothing and even today there's still almost nothing. based on my educated guess, there might still be some leftover stuff like Brain remixes, Atlas Shrugged, The General... and that's it, nothing else has been at least remotely put together.

edit: adding to variant 1) - the intentional tracklist might also have something to do with the leaks, to be more precise: first somebody leaked some songs, then Axl deliberately decided to include those at live shows, and finally at the album tracklist.
adding to variant 2) there were many rumored or half-confirmed song titles during the 10 years in the making. most of them might be just bogus fake titles, or absolutely pure speculations that somebody from newspapers put together.

yup. and it's a HUGE problem, because the song itself is FUCKING groovy. and that idiotic intro has killed it off airplay. if they had at least made some radio edit, but I think there was no such release.

similar maybe about the rest of all songs until 2002 - remember that only Axl and Dizzy are still in the band to remember that era. Fortus jumped onboard only after the ball seemed to have started rolling a bit. but the most important guys from that era (Freese, Pitman, Finck, Buckethead and even Paul Huge are out for nearly two decades already). nowadays' band hardly gives a shit about late 90's, I think.