The Witcher 3: when modding goes wrong

By the time Witcher 3 came out I was big into open world role playing games and also big into modding those games so a small way into the game I got sick of a few annoyances and logged into nexus modding site and proceeded to do my thing. Sick of applying oil before each battle? No problem, there's a mod to apply the right oil automatically and one to make oils have more uses. Tired of repairing weapons? Ok, there's a mod for that as well. Having to go to a signpost to fast travel? Ha, there's the mod I need, Fast Travel from Anywhere. It was making things move along at a bit faster pace because Witcher 3 can get a bit fetchy on some quests and the ride out is ok but going back is a pain and the signposts are a bit scarce. Oh well, it's fixed now on with the game. So I played on and got up to near the end of the game. But I couldn't find where to go. I'd run out of quests and nothing was obviously standing out that could point me to finishing the game. Even searching online got me nothing. It was obvious my game was broken and the internt wasn't telling me why. I eventually gave up on it and forgot about it. Then I think it was the DLC came out to raving reviews. I decided to give this game another go and try to avoid the game-breaking bug the shitty those developers had left in the game. So I go back to the mods page and have a quick read of the changes to my favorite mods. On the second page a lone guy is complaining that he used the mod and fast traveled after a mission ended to save himself running through the tunnels and missed a trigger at the end of the tunnels that started another quest which opened up a huge sidestory and major part of the game. The plotline could basically be ignored if you wanted to, but only if the game knew you had progressed past checkpoint at the end of the tunnels. Since there was no way back into the tunnels after the quest ended, I was basically screwed.