I have the same boat. Also couldn’t figure out how to gain access to the switches or the panel. The mechanic at our marina showed me that you need to unscrew the vessel view above the panel. This will give you the access you should need.
Just took position of 2018 335SY. Checking out all the systems found that the wet bar faucet is not working. All other faucets work fine. is there any trip with the wet bar faucet or thoughts on what it could be.