I will try and clean all the residue (hard to reach) and see if the housing remains dry.
I am guessing it is not the hoses - they connect to the, (for lack of a better term)- "thinner" part of the valve well below the suspect area. That suspect area is right below the wide part of the monovalve (where the inserts reside).
I need to check further, but I do not think it is the aux water pump either -
The leak, if there is one is only from the passenger side of the valve. That would rule out the aux water pump, would it not ?
thank you all and I will keep you posted.