Yeah ... its leaking.
48 hours later, no one using the pool, cover in place the whole time ... water down 3/4" and liner floating around the bottom corners and wrinkling at the top again.
Pool guy gave me the number of the "diving dude" ... who says he will find and fix all the leaks using a magnified diving mask and dye for $200.
Part of me says "pay the man", whilst the engineer me says "you haven't even tried it yourself yet ... why are you giving up so easily?"