Tom,
This could be an easy repair. Do you know the extent of the damage beneath  
the fiberglass? Or did it just rip out the screw from the fiberglass. Sometimes 
 simply filling the holes with epoxy and re drilling will solve the problem. 
As  Ed mentioned, I do have an old article published in Sail magazine on 
repairing  cored decking. Let me know if you need it.
 
Rummy