flaw in manufacture
I had the same problem on my oday 25cb 1975 model. The problem was in the manufacturing of the boat. They used raw wood without encapsulating/sealing it from moisture. Grind out the old rotten wood, clean with acetone (open hatches for ventilation, cut a piece of wood, spruce would be fine, the wood should be 6-12 inches long, or whatever you like, have it wide 3-4" or so, and 1-2" thick. Gring/sand it to fit the radius and angle of the bow as best you can. go to walmart and get bondo, or fiberglass reenforced bondo stuff, bed your new wood coreing with this stuff-it will glue the wood in place. Then when dry fair it in with a good filet to the existing hull surface (you have to grind/sand this surface then wipe with acetone to remove wax) then just cover it all with 1-2 layers of glass with resin or epoxy. Then redrill the holes for the new eyebolt-you are gonna use a new one,right. Seal everything with 5200 or something similar, like the previous post suggested. And there you have it. The idea is to spread the load over a large area, so if you have a catastrophe it will rip the entire bow off the boat instead of just the small area around the eye. Oh, yeah, a backing plate, or large fender washers would be called for to help spread the load.