GrantA, I was going to say that I hope those who have already paid for the issue to be sorted, have some sort of evidence to produce. Either as you have a receipt with the reason stated or the person who did the work willing to sign a statement explaining the reason.
I had a bit of a play with my car today, trying to get the water to leak out from under the car. I took it for a decent run up the motorway, then parked it nose first in the garage, set the Climate Control to HI and left it running. This is the result -
At this point the engine wasn't producing enough heat to keep the engine at operating temps, as well as heating the cabin so I was forced to put a brick on the accelerator to run it at a high idle.
That is a considerable amount of water that has come from my vehicle somewhere. I haven't been out in the car yet to see whether the sloshing sound has gone but I will report back later on that.