I am hoping the spray foam will not get wet, as both the outer and inner layers of fiberglass are intact. Also, after I cut the dried foam from the access port hole, I did seal it with "Marine Goop".

If this repair does not hold up at the beach, I will probably try to cut out the inner fiberglass layer and the damaged / re-foamed areas from inside the hull through the access port. If I can do this I will then reinforce the area with an all-glass, multiple layer repair, or add another layer of glass to the outer (gelcoat) layer from below, replace the damaged foam, and put a couple of layers of new glass on that and attach/seal it to the existing inner glass layer. (Unless someone has a better idea?)