Since you can not climb into the storage area,
Idea #1 - Put a light in the storage compartment, take a smart phone, set it to video, put it inside the storage area, aim it at the door/wall and close/lock the storage door and spray the out side of the storage door area with a hose. When finished, review the video to see if you can locate the leak.
Idea #2 - Put a bright light inside the storage compartment and when it gets really dark outside, turn on the light, close/lock the door and look around the door to see if you can see any place where light is coming through.
If there are areas where the cable connection is, or shore power opening do the same.
2013 Jayco Eagle 284BHS
250Watt Grape Solar Panel, MorningStar MPPT 60 Charge Controller
1500 Watt Ramsond PSI, 2 Trojan T145 Batteries (260Ah)
2 - AirSight Wireless IP Cameras (used as rear view cameras)
EnGenius WI-FI extender, D-Link wireless (n) modem
MagicJack Internet Phone
2012 Ford F150XLT, EcoBoost w/3.73
157" Wheel base, HD Towing Package
Our Solar Album http://www.jaycoowners.com/album.php?albumid=329