Hello
This seems to be solved. It was the stupid windows power management!!!
I didn't even think it through at the beginning, that it has to be a windows thing since my laptop works flawlessly in linux but then it occured to me.
This was caused by a power settings which puts the laptop into hibernation after 300 minutes (5 hours), this even happens when the laptop is in sleep mode already! This is why windows woke the laptop up randomly the middle of the night, however sometimes it did fail to hibernate afterwards.
That is why it looked that *some program* wakes it up from sleep mode.
I hope this will help others in the future too who run into this issue. This is a gaming laptop what you don't want to carry around or hibernate and all that. You just open it play, put it back to sleep mode and do it again next day
🙂