I just repaired the curbside skirt on mine this past weekend.
The "brace" that keystone had put in was a 3/4" wide strap with the side edges bent into a quasi U shape.
They had put one #6 self-drilling screw through the brace into the aluminum bar at the top and that had broken off. For now I have 2 #8 self-drilling screws holding it to the camper body rail and reinforced all the screw heads in the skirt with washers.
I figure I will need to do some more bracing to it, but hope this gets us through the rest of the season. It is too frickin hot here to work on it
-Brian