Well the saga continues if anyone is wondering. It’s obvious now that it’s coming from around the main drain somewhere. Confirmed both visually and by hydrophone. Only problem it’s been patched with putty once, then completely cut around and repatched. Yet the leak still remains. This can been seen in the pictures below where it’s dry, then progressively starts to get wet from groundwater on the backside.
At this point the contractor is starting to waffle and say things like well all pools leak a little......well I have a stinking puddle in my backyard, I don’t think that’s acceptable. Also complaining about the high water table, which yes does exist, as being a reason for the leak being hard to fix.