Unless, of course, the photographer wasn't the one who uploaded the picture to Twitter in the first place, but then why is the case hinged on whether the photog's name was cut off in the re-tweet, versus just the picture being copied by someone without permission?
And, going after the re-tweeters seems like a fundamental misunderstanding of the service. They aren't really copying anything, that's all a mechanism of the platform.
If I were Twitter I'd be counting my lucky stars that my largest userbase is in the US where, as broken as our copyright system is, I can't imagine this wacky judicial reasoning prevailing.