If it has a companion app for a phone (which this appears to be), you could easily have the phone do this for you. Not unlike setting up a wifi hotspot.

Just have support walk them through a menu on their phone for an "advanced" feature they just tap on, then hold the button on the microwave. Voila!

(Granted, I did tech support long enough to know this isn't easy; if someone can follow instructions, however, it should be doable.)