Update:
Thank you Rich for pointing out the access panels. I had no idea and yes I have them like you.
Based on the newly discovered access panel I was able to reach the broken pipe. While this is the inflow from the bathroom sink, it is also the low point on the tank (they are sloped to help draining). I am guessing since the tank was at 100% capacity (or very near), creating an opening in the top would allow a fair amount of volume to drain out.
I tested the other inflows (kitchen sink & shower) and there does not appear to be any additional leaking, leading me to believe this is the only break.
I also closely examined the black water tank (visible from the exterior access door) and it appears to be resting on the frame. I can not see any evidence of any strapping, indicating it is suspended. I can see about 80% of the tank (top, part of the bottom and two sides). I can also see about 10% of the grey water tank through this access door and it to seems to be sitting on the frame.
From the interior access panel shown below (the pipe in question is the bottom or left pipe), I can get a fairly firm grip on the now empty grey water tank. I can not move it, giving me some confidence that it is sitting firmly on the frame as intended.
If this is true, there must have been some unintended upward pull by the bathroom sink inflow pipe that is now separated / pulled away from the tank. There is a 1/4" gap between the pipe and the tank giving me further confidence that this is an isolated issue and there has been tension here for some time.
Given all of this, the fix would be rather easy=Cutting the inflow pipe, adding a longer length to reach the tank and reseal; however, I do have an extended warranty and the benefit of an Adventurer dealer nearby. I think I will get a second opinion. I have an appointment next Monday.
Finger's crossed this is the scenario and the repair goes quickly. My worst fear is any delay in the 2013 camping season.
Thanks everyone
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