My microwave took a dump in my 2018 Greyhawk. Turned it on one day and i heard a huge pop. As per Jayco they asked me to go out and buy one and they would cover it. I replaced it with a no name brand from lowes. Had to find something that would fit and that was light. Cost was about $150. I had my local camping world do the install and Jayco covered the expense. My first long trip we took and the microwave decided to unhinge from the wall and nearly came crashing down.
We are not big microwave users so this is what I did. Bought a stainless steel vent made by Cosmo for $100 and put it up. Installed wallpaper and gained a free spice rack in the process. The vent has an led light and 3 fan speeds. It is much more quieter then either microwave that was there and does a way better job. It also draws way less power obviously. We always carried a toaster/ airfryer with us so that's where we heat up any food.