I have a question: what is intrinsically wrong with having eyes out of focus? I think that is preferable to closing them in the same way that sitting seiza is preferable to sitting on a chair: none is optimal, but it is always better to do the best we can.
Second, I say that our eyes are focused (meaning, not fuzzed over, or crossed, or "out of focus" in that way), but we are looking at everything and nothing. Yes, they will wander around sometimes, or rest on a single point sometimes. But we do not let the mind become tangled in a chain of thoughts by that.