If your unit doesn't have any 240 volt loads, it may be OK to tie the 2 hots together on the generator side of the transfer switch.
If you've ever used a 30amp to 50amp converter 'dogbone' pigtail to use a 30 amp campground pedestal, that's what it does.
Best to double check with Jayco, though.
2016 Greyhawk 29MV
2009 smart toad
Meddle not in the affairs of dragons, for you are crunchy, and taste good with ketchup.