She's got to be a mosaic/chimera. I've never seen merle act that way. If the dog is red, it'll be red merle. If it's black, it'll be blue merle. Red with blue merle makes no sense.
Uh, there's so much wrong with that article I don't even know where to begin. A chimera is not two different SPECIES, and a black lab and yellow lab are certainly not two different species, not even different breeds! I'd question the cat, too, if it didn't say she was tested as a chimera, since it's a female. I sort of question it anyway just because the rest of the article is crap...