its funny that you bring this up because i have just finished collecting all of the police quest games and i keep feeling it isn’t complete because i have this weird memory of their being a cd version of police quest 3. i never owned it, but i seem to remember ads for it.
i think i can even remember the specific ad. it was for sprint, and if you signed up with them you could select 2 sierra cd games from a list that they were offering. get this, leisure suit larry 5 was also on the choice list! and this wasn’t just a text list of games, there were actually pictures of the games on cd.
i think what may have happened was that it was released on disk first, like almost all of the other sierra talkies. then maybe there were plans to put it on cd, and they started advertising it before it was made. then it got cancelled. i am probably completely wrong since im basing this on my old memories.
or maybe the games were just released on cd, but not actually talkie games.
good luck. if you find it, let us know.