Not sure this will be of any help, since it appears this is after market, but here goes.
My deck light switch is located on a separate DC electrical panel to the right (just out of the picture - sorry) of my AC panel on my 2009 H36. I presume that its an after market panel installed by the dealer - it looks the same as the other panels, but has just a few DC accessories wired to it, including the deck light. I suppose it would've been obvious to you if that were the case on your boat, but in the event there's some unlabeled switches on a non-factory panel, I throw this out there.
On my MH-37, and the previous 39, and 38 models, the deck light breaker is on the DC Main Panel. I didn't have a deck light on my 2011 33, but the compass lighting would only come on with the running lights.
A former 356 owner was Jim Seamans whose 356 was called Java. You can find many articles on the work toner on his boat. Who knows he may have covered this in the numerous articles in the archives from Jim. He was a customer who contributed a lot. However , I lost my friend years ago which was a great loss. FYI