There is a Wiki Entry listing all things required. You can compare that to what you remember doing.
https://thelongjourneyhome.gamepedia.com/Hero_Syndrome

I take notes to complete 57/57 tasks. I don't know where they are missing. Is there any file that can be opened for viewing?
If not, I might have to do the 57/57 mission again.

Oh, so you should already have it?
i double checked, there are no reports of it being bugged, as well as steam stating some players having it unlocked.
Unfortunately i do not now of a way to check, since that cupled with steam stuff.
You can go through your achievements and cross some of the 57 off at least.
Ill see if i can dig something up.

I do n’t have any hero syndrome
The options in the game show that I only solved 98% of the problems.
Now I can only do it again to see if there are any omissions