Here are the reasons for Long Rest Times Sensitive Events:
1. Yes I understand what you are saying. But you are trying to place a linear restriction on a non linear game. What if the player wants to investigate the owl cave, or the spider cave before this? What if they rather investigate the bog? Each have heavy combat, therefor the need to rest to recharge your abilities. Maybe run around and get in some more conversations to trigger the dream and possibly use your illthid ability? This is a totally different game than say XCOM where the entire game is basically based on the use of time.
2.So? Not to mention you are trying to say this is going to happen after the starting area? Maybe the combat will get way more difficult once you leave the starter area and potions and food will be more important (which Larian is known to do just look at DOS).
3. Short rest is 2 chance to quick recharge before needing to long rest.
4. Seriously, do you think that the majority of players give their tertiary NPCs much after thought? I mean they don't even leave until after the main battle and finishing the Druid questline. I am also thinking, they are another side quest once we leave the starting area.
5. I know that is seriously important to you, and that is cool, but I am sure there is plenty of players that it is not a game breaking loss. More of a cherry on top.
I get what your saying after this list, but I just don't agree. That seems like something that I would find restricting. Every RPG is different to some degree, but I do not think there is some epic difference between this RPG just because it is based off of WoTC content.