I don't think it matters who translated it. As Stevens notes in his book, the doka are meant to have meaning on several levels. In other words, it's not the literal translation that's going to be important, it's the nuanced subtleties.... and as usual in Asian writings, you can understand the subtle implications only if you already know them. Because a certain translation *sounds* good or "flows" nicely, is sort of beside the point.
FWIW
Mike