It does seem unfair. With the benefit of hindsight, it's probable that Andy knew his back wasn't up to a full on Summer schedule, and was likely to need a break again soon, so knew he had no chance of boosting his rankings.
Then again, whenever anyone makes bold public statements and judgements without the full facts, they run the risk of putting their foot in it. Moya may not have known that Andy was playing injured, but he must also have known he didn't have the full facts. He must have known Andy was injured during the clay season and it was a long-standing injury.
That said, he's hardly alone. There's plenty on here who have made more than a few foolish statements, with some even being dismissive of fans who (correctly as it turns out) gave the benefit of the doubt.
Deciding to run that interview now, when presumably Moya has twigged he got it wrong, is peculiar. Perhaps he thought it would stir up a bit of controversy.