There is zero problems running fuel, oil, methanol, methanol/water, ethanol, etc. into the supercharger. The fact is that the rear bearings will never see the methanol unless the methanol gets sprayed when the motor is idiling or not running. The vacuum and air motion going into the SC is dramatic enough that only vapors can get to the rear bearing. The front bearings have double lip seals that prevent anything from getting to them. Liquid in fact helps increase the compressors performance in many area's, first it works as a sealing agent, closing the clearances which increases efficiency (industrial compressors are run with no gears and just oil between the rotors). Second, there is certainly a cooling effect from a liquid, whether it's an actual phase change or just the heat of vaporization (cooler liquid absorbs heat), the air charge does cool down. Methanol of course has incredible cooling properties.
Just wanted to clear up some of that.
Thanks,
Dustin Whipple