He has a bathtub with a hole of exactly that size.
14+ Fix Hole In Fiberglass Bathtub
Gif. Here's an attempt to repair a hole in fiberglass. Holes or cracks more than 1/4 inch wide will need fiberglass cloth repairs.
HOW TO FIX A HOLE IN A FIBERGLASS BATHTUB - YouTube from i.ytimg.com
Maybe you two can work something out. Unfortunately, my old rs (which is over 30 y.o.) finally gave up the ghost and a key part to fix it is no longer available. Most all fiberglass tubs have styrofoam support rails adhered to the underside when new.
This will help support the floor, preventing future cracks.
A holed fiberglass sailboat or canoe looks bad, but unless the boat is structurally damaged, it's easy to repair. Being able to cut nails off of old electrical boxes, cutting holes in drywall, or even. You might spray some great stuff. Larger holes may require addition layers.
