Thank all for the responses. I did get CD's "official" line as well:

"We reinforce our kayaks with tuff-weave material (50% polyester and 50% fiberglass). Depending on the type of material your kayak is made of, the material in the cockpit could be kevlar or fiberglass. We use polyester resin in our factory to laminate the fiberglass or kevlar in the kayak. We do offer the tuff-weave material through our accessory department"

Does that change any of the advice so far? I guess they were not specific enough to tell me the actual material on the inside.... But since the repair is more of a prevention of further/future damage rather than fixing something that's really broken, I think the 2-layer E-Glass patch seems easy enough to do and available locally.

Thanks!