I guess the mistake is, he dug his heels in and then refused to let go! I don't follow all the ins and outs of what is going on at Madrid, but I know that Zidane has no interest in him, so did he Bale decide to stay as is his right, when Zidane left thinking his problems there where over?
So now, much to his dismay I guess, Zidane came back, and now he's in a situation where he knows he won't be part of the plans there, but he's a few more injuries down the line, and his options are limited.
What can they do now? It's hard to see them finding a buyer. So they have to find a loan for him? And stump up a large portion of his wages? Or just pay him to play golf for the next two years.