Missing meows

[Nihyl]

What flag is to reset the failed quest?

 

[WolframL]

Unless you want to permanently enfucken your run for bug reporting purposes, it's generally better to look for an auto-save from before you did something you regret, or make multiple local saves since it's not like there's a limit. Also, messing with event flags can really screw things up.

 

[Nihyl]

I don't have a save, and don't want to replay so many things, so I am trying to find this flag to reset this.

 

[Tarnakus]

There is no single flag to reset quests. Save games have array of values that represent quest progress. Sometimes changes there are not enough to truly reset everything.
Here is how to do it:

Save edit:
Save to file and open it with text editor.
Find array called quests (ctr+f and type quests) then count from 0 to 14. You will have either [0,1,3] or [0,1,2,3] (depends if you saw heat scene). Delete everything in between 14th brackets so you will have only []. After loading the save you should go to the quest tile and you should have "Hollow" button (after loading check quest journal you shouldn't have Mad Cow entry in completed). Quest tile: Second red tile on the left from Marefolk Village with Brint.

Beginning of quests array and how to count (I added space for better visuals on empty brackets):
"quests":[[0,1,2,3],[0,1,2,3,5,8],[ ],[ ] ...
[0,1,2,3] - 0
[0,1,2,3,5,8] - 1
[ ] - 2
[ ] - 3
etc.

Above is about Brint->Brienne quest - experiment and find which quest is Missing Meows.

Edit: I remember correctly that someone already asked about that quest (and I found it in my posts history) in your case it should be from 0 to 8 - the counting part.