I had the same thing happen to my previous trailer. If wanted, you can make a an access flap in the bottom of the corrugated plastic underbelly cover so you can repair the damage. Once you repair the wiring, make patch to go over the cutout. You can buy sheets of plastic at many home improvement stores.
Seasonally in the Grand Marias, MN campground
On the beautiful shores of Lake Superior
2012 Ram 2500HD CTD