Well, the trusty Nomad has been repaired. I drilled out the ends first to keep the crack from spreading any more. Then I shaved some plastic off of the cockpit rim and used it to weld the outside of the crack (which was in a shallow valley in the boat, a water-shedding line of some sort) and to fill the holes I'd drilled. After getting things tight on the outside, I then Whaley Welded the inside with duct tape and heat. It's the same process I used on my Phat and it looks like it should be bomber, especially on the Nomad where the crack is still full-thickness. The fact that the crack is high and away from heavy stress areas and the waterline is also a benefit.
I also noticed that the ass dimple that the boat got from Gorilla has popped out, just due to the effects of some warmth and the memory in the plastic. Looks like the Nomad should be ready for the Colorado steeps.