Speaking of islands I noticed an earlier quest about finding a master armorer which involved a nice boat ride to the frigid land of Undvik. One of the more atmospheric locations I’ve seen thus far with all the wind and rain, busted up boats, etc. Get the sense that some shit went down here. The numerous barrels full of ashes is a neat if unsettling touch.
I'm wondering if you might have missed something....
Spoilers I guess maybe?
But.. if you're already at Kaer Morhen then you must've completed the main quest line that starts with the wake and ends with identifying Uma as the next clue. After the wake you would've spoken with Crach an Craite who askes you to help his children, one of which indeed takes you to Undvuk.
Perhaps you visited Undvuk before doing the wake? That would prevent you from being able to pick up that quest.
In fact, that quest- The Lord of Undvuk- is both my favorite quest in the entire game and is also one of the earliest ones put together. It can be done very quickly or you can let it take you down side adventures and I just love it. Definitely if you want to do it and haven't you should do that before Isle of Mists. Same goes for the other such quest on Spikeroog. But even before doing those I highly recommend the contract Phantom of Elsberg because only by doing that one BEFORE the whole An Craite side quests resolution quests, you get an extra very cool side quest that is also one of my favorites.
Yes, the section of Skellige before Isle of Mists is my favorite part of the game.
So far I counted 92 quests done of which maybe half dozen or so are contracts. So if might switch gears and do a few more of those. Also I’m missing the quest queue for the third part of the Wolf School Witcher gear. I have part four though, so I must’ve missed something.
There were some bugs with wolf school gear at some point (as it was really part of free DLC) but I think that was all fixed.
There are some maps available from the master swordsman only after you complete his questline so it could be those. Also it is possible to unlock a witcher gear treasure hunt quest by finding one of the diagrams on your own (for example I remember finding a high level Bear school gear diagram in the cave that was the home of the bear that attacks Princess, the Pellar's goat). So maybe you did that for one of the master diagrams for wolf.
My recommendation is to just pick which gear set you like, you're far enough along now that you don't have to chase everything. If Wolf School is your preference, that's cool, and there's not shame in just looking it up online. I do always recommend doing the base gear quests for all the witcher gear just because they're fun- some excellent locations to explore and fight at. But only chase the upgrades for the one you care about.
Speaking of misses, I also have seven failed quests but am too far along to bother with going back to early saves on this playthrough. I guess a wiki would be needed if there’s a trophy for completing all quests since I have no idea what triggered the fail states, other than perhaps getting distracted by other quests in the middle or something.
Don't worry about failed quests. Sure, when I replay, I never let myself have any but that's just because I know this game by heart. There is no trophy for completing all quests or not having any failed ones. There are specific trophies that you can't get if you fail (or skip) particular quests but that's something to worry about on a replay. If you're curious about specific quests you can ask me of course.
I'm guessing you failed Gangs of Novigrad- that is a notorious one. This is in Novigrad after you the fight where you're in a towel and you have to chase down Whoreson Jr. Cleaver offers a violent brute force method and Reuven suggests otherwise. The game doesn't really explain that in order to complete Gangs of Novigrad you have to speak with Cleaver first then meet his goons at each of the hideouts (casino and arena). But if you ignored that and infiltrated each place using the more subtle and, frankly, fun ways of playing gwent and doing an arena tournament fight, you will fail it. Or if you try to attack with them and they all die in one place, you fail it. It is possible to not fail and still sneak but this is advanced Witcher 3 obsession nonsense and nets you absolutely nothing except the OCD-like obsession with not seeing red text in your menu.