It's a mindfield indeed, we got Bracken before we found COL and now realise her breeder was a rather commercial venture. We didn't know much when we were looking and didn't really know about working cockers. It was only when we got Bracken's pedigree and we noticed FTCH in her pedigree (and found out what that stood for..) that she had any working cocker in her.
It doesn't sound like there was a good 'breed' reason for the owners to mate their two dogs together, but to me temprement is as important as breeding. Like I said somewhere, you can't be sure what the dog would resemble in terms of coat/ looks - could look worker, could look show, could be somewhere in between. the most important thing.
Have the dogs had any health tests done? I really wished I had known about Optigen testing when we got Bracken as there is always the risk of her having these hereditary conditions, which better breeders would have tested her the parents for.