Hi,
I have a 1999 ML. I checked my all data and their seat removal instructions are:

Remove Head Restraint
Remove cap from seat rail panel (the plastic running along the sides of the seat)
*Adjust seat height control until bolt on belt end fitting is visible.
Remove bolt on belt and fitting
Detach belt end fitting
Remove bolts on front seat fastening
Adjust front seat forwards
Remove bolts on rear seat fastening
Detach electrical connector block from seat (looks like it’s in the rear of seat)
Remove front seat
Install in reverse order
It looks like there are 4 bolts, 2 front and 2 back that hold the seat in. The bolts are all internal torx heads. From the illustration given, it looks like the front seat bolts are further back then the front of the seat where the fascia cover is. Is it possible to check under the carpet at the front of the seat to look for them? From the illustration, the front seat bolts look like they bolt to more of a vertical plane, like a frame rail of some kind, not to the horizontal plan of the floor.
I’m not the greatest with electricity, but I’ve always found that most of my problems with anything electrical are in the switch. Is there anyway you could just remove the seat switch from the equation by disconnecting it, or swap it out with the other side temporarily (I know it would be backwards and you couldn’t install it) to see if the short still occurs.