I'm currently having the exact same issue - TPS65994 replacement didn't solve it.
The laptop is currently back with the owner with new FETs (mine are from Mouser) because I didn't have time for more detailed analysis.
I expect to get it back in about a week with the same issue for the third time, then I can investigate further.

What's weird is that the gate voltages don't reach high enough to fully switch the FETs on, so there's always about 1V VDS which can produce 2.5W on an empty battery.
No wonder the FETs almost desolder themselves.

According to...

Re: New Members - please post your introductions here

Hello! New member from Austria. I have downloaded some schematics and found helpful stuff in older posts.
Now posting here to be allowed to post a new thread