I had some bad luck and fractured the bottom of my Starboard wood iSonic in an underwater rock. I removed all the loose bits from the fracture, and there is now an about 5 cm x 7 cm hole in wood sandwich, which leaves the EPS core exposed. The EPS core has also a some small missing bits. The damage is situated at about 60 cm from the rear of the board.

I'm looking for advice in how to repair such a damage. I was planning to fill the void with urethane foam up to the level of the upper part of the sandwich core and to laminate 3-4 layers of carbon on top of the urethane to replace the wood and glass outer shell of the board. Would this kind of repair be strong enough?