: Any thoughts on
: remedies?

some other ideas to consider

put a cam strap around the yak at the offending ribs and from the outside push on the rib and tighten the strap until the rib is fully seated. the strap should be just off c/l of the rib.

take and awl and spread apart the fibers of the skin about 1/8" diam or more if possible and drill thru the gunwale and rib from the outside. syringe in some epoxy or waterproof glue maybe working the clamp up and down a bit. push in a short bamboo skewer(thickness of the gunwale). move on to the next rib and repeat. release clamp tensions together , push the fibers back together, refinish w/ your sealcoat in these tiny areas.