We have a Waste King 8000 installed below a 10" deep undermount sink. Works perfectly for years now.
I mean, I can feed it corn cobs and chicken bones and it doesn't break stride. Pretty quiet, too.

The problem is that the height of your drain pipe above the floor is too high and needs to be lowered. This will require tearing into the wall behind the sink. I would add that the Insinkerator Evolution has a drain slightly lower than the older Insinkerator models, so that is an additional height loss.

I have an Evolution mounted to a sink that is 10-inches below the countertop surface. The disposer drain barely adapts to a normal trap connected to what I believe is a standard height drain pipe. Although there are limits to how low the trap weir can can be (2 feet max below the basin, so below the floor is too low), I am unaware of any code requirement for a particular point of exit at the wall. I suspect that the height normally set by plumbers is intended to provide maximum space on the cabinet base surface.

kas