Need help fixing Nintendo Switch fan problem

Hello, like already said in the title I have a problem regarding a friend‘s Nintendo Switch. So, basically the fan wasn‘t working anymore. My friend‘s brother always played Fortnite on it until the fan stopped working and eventually the Switch would always overheat and go into Standby.

I though it would be an easy fix if I would just build in a new fan. Didn‘t work. The battery was also at the end so I also put in a new battery. Capacity was kind of fixed, even though the battery would decharge pretty quick since the heat doesn‘t get blown out.

So I still face the same problem after switching out the fan and the battery. My only theories left are:

1. ⁠onboard problem which I can‘t handle since I don‘t have the equipment to measure voltage etc.

2. ⁠I accidentally broke the lever from the socket of the FFC ribbon cable which connects the fan with the Switch, but only the lever. The pins seem to be fine. But afaik the lever isn‘t needed to actually make the contact with the main board, it just keeps the cable attached, right? In fact I didn‘t broke the lever but I accidentally took it off in flipping it to the wrong side apparently? (Never happened to me before lol) Afterwards, I couldn‘t reattach the lever anymore and since it‘s so small I lost it 😭

So I don‘t know what to do anymore. My friend says it‘s okay if the Switch isn‘t fixable but I just want to be sure that it‘s not because of the broken lever. I hope you guys understand my problem, I had some trouble stating all the facts and explaining the problem. Thanks for all help ^^

Copy-paste from my Reddit post in the ifixit-Subreddit: https://www.reddit.com/r/ifixit/s/o2TtUk...