I've enjoyed the boat very much and have always encouraged other members of our club to purchase Hobies, but if this is what I have to look forward to, I may need to rethink the advise I give to people.
(to Matt Miller) As a representative of Hobie and this board, you are certainly not enticing me to do business with you again.
Mel, I'm not sure I would want to take advise from someone whose opinion about his boat hinges on the style of answer he gets over a pin hole! Perhaps you have some other agenda I don't understand.
Nevertheless, here are a couple of ways you can fix that pinhole and perhaps improve your frame of mind.
1. Plastic welding:
If you have a solder gun (or similar), you can melt some matching welding rod (which "not enticing" Matt Miller has offered to make available to you at no charge). Best to practice on a scrap first. Here's a small sample hole being filled:
Carefully heat the area where you want to deposit the plastic then melt the rod into it.
Sand or file the surplus off and it should look almost as good as new.
The only good bonding epoxy I've found is 3M ScotchWeld DP 8010, available from several industrial suppliers. It's not quite as easy to work with as most epoxies, but if you're fairly handy it's not that bad; and it's the only one that I know of with excellent bonding strength on PE. There are some other epoxies that don't bond as well to polyethylene but may work well enough (on a non structural application) if you rough up the area with sand paper and clean thoroughly with alcohol. West Systems G-Flex claims to work with this application but I haven't found it's adhesiveness any better than most other epoxies. If you have something sitting around it might be worth a try.
You can further protect your skeg with a variety of replaceable tapes if interested. Good luck with your patch job.