Mcp23017 getting very hot within seconds

Sorry, not answering to that.
Your name totally suits you.
Pointing out false things and insisting on them, although I tried to show you it's the same thing.
Maybe the PCB is a mess, but interesting that you can see that only because one IC is rotated 180 degrees.

Saying "friend" (which I did not say a single time) like I am trying to hide it was me who did this.
And as I already stated, there are no shorts and I checked all pins multiple times.

So thank you for your help so far, but please do not spend any more time on this.