The seam in your picture certainly looks like a good candidate for a leak. The gap looks like it may have widened for some reason, not just the aged sealant.
I have looked at pictures of the 845 online, and the LPG compartment is below the fridge compartment, right? In that case, look at the frame of the LPG compartment door, if the seal around it is in good order, and if it the inside lower edge is sealed well or if the sealant looks similar to the fridge compartment you pictured. The "floor" of both compartments was dry?
You might also remove a screw or two from the lower outside edge molding below the LPG door and see what they look like and if they appear to be wet or dry.