There is no wood in that area… those non resin impregnated fiberglass fibers were soaked with water. The only wood that I know of in our boats is around the pop up cleats and the swim deck.
Your fix isn’t going to stop the other issue of water flowing freely into and out of the anchor locker which will keep your chain and rope constantly wet. I even seen the bow rider version of the 21’ boats have water flow out of the anchor when they come up onto plane.
My suggestion is to order the parts
@drewkaree listed in his posts and fix that drain properly and get the little plugs I linked and eliminate this issue once and for all.
With some more simple effort and a some not so simple you’ll be able to have a dry bilge;
-seal up all the cup holders, seal off the drains for the two forward most cup holders as they drain into the bilge or make them drain onto the deck the way the two cup holders drain onto the deck, the cup holders on the transom also drain into the bilge so those drains can get sealed off too, and secure the drain hoses as well. The two cup holders on the storage pods will leak water into those storage areas. Use a sealant like Three Bond 1211 to seal the cup holders.
Use a bit of silicone to glue the stainless trim rings on the cup holders or they will disappear.
-Only the forward two rod holders drain over board the others drain into the aft storage compartments then into the bilge. T-H Marine makes some universal rod holder drains that you can install then route drains onto the deck, the transom vertical rod holders (as well as the transom cup holders) will be harder to run the drains for but it can be done. Seal up the mounting surfaces with Three Bond 1211 or UV stabilized 3M 4200, either of those products can be removed but I like Three Bond 1211 (Aka Yamabond) as it dries flexible.
-Replace the two stock plastic scuppers, one from the live well drain the other from the deck drain with stainless steel ones from GemLux, these are the not so simple tasks but are well worth the effort. I’d also suggest replacing the stock deck drain hose with smooth hose instead of that spiral wound stuff, the smooth stuff is MUCH easier to get to seal on the fittings.
-Make sure the L head deck drain fitting is well sealed against the bulkhead.
-While you’ve got the aft bilge opened up check the snugness of the live well fittings (and all the other fittings and hose clamps-replace any rusted clamps) Snug not tight these are plastic fittings. Also make sure the little black hose is connected to the aerator suction fitting on the live well. You’ll see a little black fitting above deck next to the live well that says MAX AIR on it, this where the other end of that little black hose connects to and where the aerator gets its air from.
-Clean out tray. Use seal and peal to seal the tray AFTER THE TRAY IS INSTALLED, you do not want to glue the tray down! Get a mechanical hatch riser from Jet Boat Pilot. Before you install the clean out tray, get some blank fittings and remove the drain in the clean out tray, it’s not needed on our boats as there are two big channels one on either side that allow water out. Whike you’ve got the tray off it’s a good opportunity to clean this area, let it dry and then spray it all down with silicone spray as a final task before sealing everything up.
-Have a look at the clean out plug seals, if they look rough replace them. Spray silicone into the areas that pivot to ease installation and removal. You can spray silicone onto the seals as well or use a bit of pool pump grease on them. The clean out tubes will usually have water in them during use.
Whichever sealant you use, use copious / enough amounts so that it squishes out from under the areas that you’re sealing up-except the clean out tray- to make sure it’s all sealed, wipe off excess.
This seems like a lot but can be done in a weekend, you’ll only need help with the scuppers, and will pay big dividends in keeping your boat dry where it should be dry and no water will come out of the hull drain plug after a day on the water, speaking of the drain plug, check the condition of the O ring and give it a spritz of silicone spray.