Mike says he can backup his iPad Air 2 to iTunes, but he can't get it to restore to a new iPad. It won't sync at all. Apple says that the backup is corrupt. Leo says if there's something wrong with the iPad's OS as it's installed, that may be true. Leo recommends backing up and wiping the old iPad. Then he should try and restore to that one. If that doesn't work, then Apple's theory is correct.
He could try making a local backup to his computer. He could also do a factory reset and let it load the OS all over again.