Why is the GM telling a story like this? What benefits are had by their framing the fiction in this way?
why is the GM telling a story where the characters actions and choices can affect the larger world in which they exist? beyond what is within an immediate 60ft radius of them or for more than the next 48 hours?
Why is the GM employing such directly relevant session notes and then saying nothing about them? Why is this particular noble so foolish as to take a vacation and not leave anyone at all who can attend to the needs of her household while she's away? Even if it's literally the medieval equivalent of, "I'm sorry, the lady of the house is out, can I take a message?"
because the events happened outside the players direct sphere of awareness? i don't know about you but i'm not constantly aware of all the goings on of the next three towns over, it might of been alluded to and the players just didn't consider it important or relevant "after you rescuing the kidnapped prince from the neighboring kingdom i'm sure all the local nobles will have their hands full clearing up this political mess of an aftermath."
i'm not saying the noble couldn't or didn't leave someone to take messages, but that doesn't change that fact that they're not there and not available for the players.
Three sessions? So...the GM has had three weeks to come up with literally any kind of compromise or alternative? This is sounding less and less like a terrible time crunch. Now, I get that preparation can be difficult to squeeze into one's life (particularly with memory being a problem!) but it seems to me that this is ample time for the GM to come up with literally anything besides, "no, sorry, that just does not work at all. Do something else."
i don't believe the world should alter itself to make sure the player's intents go off without a hitch, the world simply exists, indifferent to their goals and plans, if the store is sold out of bread for the day when i too run out that doesn't mean more coincidentally gets delivered or found in the back of the stockrooms for my benefit.
Then they are playing in bad faith. I flatly refuse to consider any argument based on players playing in bad faith unless and until it is equally acceptable to field arguments based on GMs playing in bad faith.
it is bad faith to not inform the players of the information of their absence if the players never consider to inquire around themselves if the noble might be away before they visit them? these adventurers don't exactly have a perpetual newsfeed updating them of every change to the world that might influence their plans if they knew them.
No. But that's not the problem, is it?
The problem is the GM saying, "No, sorry, that just does not work at all. Do something else." And yes, I am quite comfortable saying that it is the GM's fault that, apparently, the one and only possible response was to simply shut down the effort, and not any of the nigh-infinite variety of alternative options. Options it takes me all of two minutes to come up with.
it is not the GM's fault to run a world that continues to exist and turn outside the immediate observation of the players, sure the doorkeep could've said 'sure here's a scroll of teleportation to take you all right to them' but some of us would feel that is unlikely and contrived, the players could be given the noble's current location and meet them there after 2 weeks travel, they're still getting to meet the noble that way, the players could decided they don't actually need to see the noble all that badly after all and that fighting ring they passed down the street looked interesting instead.
not being able to use your ability to meet this one NPC doesn't bring the entire plot to a screeching halt,
sometimes we don't want to spend two minutes to come up with an alternate solution that's 'more favourable for the players' because we think the one we have makes pretty good sense to work how it does even if it's inconvenient to them.