Wire a 5 wire down draft remote motor / can this be done?
Yes, it should work. I found this wiring diagram below on Thermador's website. It's for a 4 speed blower, but it's basically the same concept for the electrician except one less wire. Black, red, and blue are the three speeds. White is the neutral. Green is the ground. This diagram might not be relevant to your model or installation and so any information that you still have on the blower would help out the electrician I'm sure. However, it should be as simply as just connecting power to the switch and then have it branch off and wire nutted together with the blower.