I have a 2011 Outback 5er and found "puddling", under the kitchen cabinet. After many frustrating attempts to find the source, wife suggested using plain white paper towels in the suspected compartment. Took her advice. (first time in 47 years we have been together
) Well, one small screw hole in the outdoor cook stove compartment was allowing water from the "non seated" faucet to slowly drip down and into the RV...was driving me nuts.
Fixed the water drip and presto; all good. I found it by placing paper towels on the entire floor space under the sink. Thank goodness it was an EZ find and solution. The paper towels quickly showed where the density of water was, then just scouted and found the culprit.
Never had a "serious" problem as we leave our RV on a site 95% of the time and turn the water off every time we leave.
Just a thought on tracking a leak. Good luck