I want to reply to you as a dive pro and as an attorney. At the shop with which I am affiliated, every student who signs up has a specific syllabus of all class sessions and pool sessions, and select among open water dive options. We have monthly local open waters most of the year, and some opt to do their open waters at their vacation destination. We do a lot of classes- one to 3 open water classes every week most of the time. IF ( and it is a big IF) you specified in your contract with the dive center what needed to be done at the time you began, and they failed to provide what was needed, you should get a total refund. If there was ambiguity, then you won't. However, if you relied on the dive shop's representations of when you could complete the class, you should get at least a partial refund to put toward certification elsewhere. The vast majority of dive centers and instructors are very reputable and honorable. I am sorry you encountered one that wasn't. Don't give up on our wonderful sport!
DivemasterDennis