Fridge slide with 3rd row
I thought about this too but ultimately just decided to install the fridge slide on the drivers side using tie downs connected to the 2nd row and the 2 tie downs toward the rear of the cargo area. It was an easier/cheaper option than trying to level out the area left by the missing seat below the trim. I don't think you lose any useable cargo space either unless you plan to build a cabinet with a drawer above your fridge. The fridge is still stable like this, even full with the slide pulled out. This leaves the passenger side 3rd row full accessible.
Here's a photo, albeit not very interesting.