Which doesn't surprise me in the least. Given that the metaborate ion is generally described as BO2-, one would assume that the general nomenclature would distinguish between 2 mol and 4 mol. With the historical context in mind it makes sort of sense to have 4 mol and 8 mol, but people entering the field are likely confused. If I were to formulate a recipe today, I'd either start with Borax and NaOH/Na2CO3, or state the exact compound in my recipe NaBO2 * 2 H2O (or NaBO2 * 4 H2O), and maybe state that the compound is sold as Sodium Metaborate 4 (or 8) mol.
Trying to be the best of whatever I am, even if what I am is no good.