That sabbatical ended over a year before team selection, not right before. If skipping 2 or 3 qualifiers is enough for him to not make it, so be it. But if that's 100% the reason, he could have been told a lot sooner.
And patdog, what is his history of being a flake? I only remember this one instance. Players often take international breaks (Howard's on one currently). If that's the only evidence of him being a flake, that's pretty flimsy. I suppose you're referring to the Germany stint, but he later had a successful spell in England, and more importantly, if struggling in Europe before returning to MLS makes you a flake, then we've got a team full of them.