The chances of them being wild caught are next to impossible. You might come across a single albino once in a lifetime, but a pair, let alone a group is nearly impossible. Plus there's not a lot of yellow labs at Lion's Cove (or anywhere else they're found for that matter), and they are a very difficult fish to catch. I spent two nights there, and the first day the four guys (working two at a time) caught maybe 70 fish - anywhere else, with many other fish you could catch hundreds in that time. Plus, the male doesn't even look like a yellow lab. His nose is way too blunt.
Almost every albino now available in the hobby is a hybrid of some form or another, and these yellows are no different.