You have a couple things to deal with when running a solid state welder off a generator. In rush current, ramp up and a clean running sine wave.

If the unit you have is 8500 watts, that's enough power to run a 200 amp TIG (35 amps of power). If your unit has a clean sine wave, but no AVR, you can start the amp low and ramp it up via the 4T or foot pedal. Automatic voltage regulation (AVR) is key in starting the unit, but a good sine wave is more key far as damage to the power supply.

Call Miller and ask if the Bobcat will run their new solid state units. If they give you the go you're probably fine.