tlee, what is that roof over top of? Are you experiencing any leaking?
I would suggest going to a commercial roofing supply house and explaining to them what your problem is. Most of your commercial suppliers have a large selection of could for specific applications. Asking for advise from the big box stores is probably not the direction I would steer you on a fiberglass roof deck. Thats something thats new to me in middle Tennessee. Stay away from silicone and roof cement though, just my
Should be an easy job you could diy. Make sure everything is clean and dry before you repair.