+ I'm not sure that there are any standards you can hold against him, especially in Kansas. In California, maybe.

+ Those sorts of cracks don't especially indicate structural problems or delamination. They may, or may not, indicate a leak.

+ You can do spot repairs, BUT, weeping like that indicates porosity in the underlying concrete, not merely in the plaster.

For that reason, I'd be reluctant to pay for the plaster, till he guarantees no leaks. AND, I'd do bucket testing for leaks from the get-go. See: http://www.poolforum.com/pf2/showthread.php/11252