The Safari cabinets are what Airstream terms "light plywood", as were the cabinets in my 2003 International AS. This plywood is amazingly light, but it does not hold screws well, especially if they have ever been removed and replaced once.
I poked toothpicks dipped in glue in some of my loosest screw holes and it helped a lot. Worst case, drill a 1/4" hole partway through the door and glue in a piece of 1/4" birch dowel. Pre-drill the screw holes in the dowels so that the dowels do not split.
I might suggest that a set of Centramatic balancers will reduce the vibration that loosens things in the trailer.
John W. Irwin
2005 Classic 28 "Sabre-Dog III"
2013 Silverado 2500HD Duramax/Allison LTZ
WBCCI #9632, TAC TX-10