Oh, I'm not expecting KoS to follow KoS timeline. That novel takes place over a month (you can literally break it down by the day). It would be impossible to do a "day to day" game of that magnitude, LOL.
Seriously, what works for a novel wouldn't really work as an adventure game. There is little in KoS that could be compared to adventure game puzzles so it's absolutely certain you would have to make extreme liberties to make something playable and fun.
In AI's Hat throwing ceremony we remained rather vague as well, as to how much time had elapsed, it would be logical to suspect that it was several months but it could have also been just a couple of weeks.
I had actually taken that "vagueness" into consideration, when putting the timeline together over on the Omnipedia actually (it was discussed in the notes in the article). It still causes a bit of a butterfly effect (to degree is unclear), creating a clearly original alternate timeline, compared to various dates given in other/official games.
Given the destruction wrought by the dragon, though, and seveal references to their being much work to be done to rebuild the land (which takes place before the Hat toss), this suggests it would have to take quite a bit of time.
I think to a certain extent some of the King's Quest games remained vague in their exact time line.
Both KQ2 and KQ5 are vague only if one doesn't read the manuals (KQ2 manual places KQ1 one year before the game for example, and KQ5/KQ8 manual places KQ5 almost one year after KQ4), or at least if one misses a references made within another game . KQ3-4 (originals) are all pretty specific when it takes place the twins are seventeen/almost eighteen (all events are shown on screen, and/or mentioned in-game text), in-game text in KQ5 places KQ3 about twenty years after KQ2. KQ7 has the specific date for Rosella given in the introduction that she is almost twenty (which works back to KQ3, putting 1-2 years between KQ3 and KQ7). KQ6 has fairly specific references to time, and its relation to KQ5. In that game all references in total are just over 6 months between the games.
KQ8 has absolutely no material offering a date for when it happened in relation to any other game.
If you meant specific calendar dates, no games give that kind of information, and only a few specific calendar dates actually appear in the games, and that's on the tombstones in KQ4. But those don't indicate how much time KQ4 has passed is in relation to when the individuals were buried.