Not sure wet
deck core will ever dry out without exposing some openings, hot sun will just condensate the
water on the
fiberglass inside. I could picture maybe coring some holes underneath with a 1.5-2" hole saw (cutting out glass only) in a pattern, just leaving it for a season... maybe it would dry out decent. (leave
hatch open when not using
boat for ventilation) or better yet install a dehumidifier when not boating! Maybe it would dry out...? Then glue the little cirlces back in and inject
epoxy through drilled holes in the top. Inject until it comes out some holes drilled in the bottom. Then seal each hole as the epoxy starts flowing out.... just a thought...?
PS: good way to see if it's dry is drill a 1/4 hole, scrape the core off the drill bit spirals, and squeeze it between your thumb and fingers. If wet,
water will appear.