I just wrote up a guide. Check it out here: https://norbez.itch.io/to-train-a-killer-first-hunt/devlog/776838/guide-to-endin...
Viewing post in To Train A Killer: First Hunt comments
Update! Also spoilers ahead just in case, hoping I format it right for future posts I make on other horror games.
Trying to follow the guide did help in a sense, so it reassured me that what I tried with Ending 2 (common) and 1 was right. I however realized that the game might've had an issue validating ending 1 because despite the route being correct and it having different dialogue than what ending 2 had, it was marked as 2/3. A related note was that on the second path for ending 1, for some reason despite doing the exact instructions, the game decided at the end to register that instead of staying still at the last part, it went to freeing the hand instead; the choice for either option didn't even come up. Pretty weird!
Ending 3 was what I got wrong with, as in I was so close to getting it right by guessing routes but also not quite, but I was able to figure it out thanks to the guide! I'd say that one is the best ending all things considered in a scary situation like this.