Repairing my Traveler Hardware just got harder than I thought

So about 4 years ago when I got my boat my traveler eyehook pulled out and I had a guy fix it for a reasonable price. He did a hack job and used dry wall screws that rusted a couple moths later, which I replaced ASAP. I had some cracking around the eye hook but didnt think it was a big deal and didnt think it went deep enough to let water in to the glass/core. The other day after sailing the hardware started to pull out, so I took out the screws to find that the damage is a lot worse then I thought. The wood core is soaked through around the hardware, and the fiberglass from the original repair was very water logged. I took all the glass out from the original repair and dug away at the core and glass around it a bit to see if it got any more dry but it didn't

I do realize I will have to take a chunk out of the boat to make sure i get all the wet core and glass out.

My question is how bad is this really? Ive never done repair like this...will I be able to do it or would it be better to hire a professional this time? (I work at West marine and im self competent but want to to last as long as I have the boat) Will i need to put in an inspection port since the damage is all the way through the deck? How common is this? and How do I even approach this???

Any advice on how to proceed is much appreciated.

Put your inspection port in. Grind the damage down to solid material. Use the plug you cut out to patch your damage. Epoxy in a backer that will support a patch then epoxy in you patch using the plug and orientate the texture and grind it off in the smooth areas. Fill in the voids and paint if desired. I just did this lady winter and posted picts of it.

Is there any way to do it without putting an inspection port in? I really dont want to have one in my boat if not absolutely
needed

I've been spending a lot of time looking at the insides of these Lasers lately. In your case here: you will probably need an inspection port eventually. It would help in drying out the boat (and to keep it dry). You would end up removing less "chunk". And work from the inside out. An epoxy like GFlex will bond the questionable material together. Save what you can on the outside.