I do not think there is any way to "turn them off". Unfortunately, this is something you have to fix. I do not own one of these but from what I understand the engine does need to come out. You may want to post on these forums and see if anyone has found a way to service the turbo's with the engine in the car. Some people can get pretty creative.

I would not be surprised if this is the reason it was for sale. Failure within one month of purchase is a little suspicious.

 

You would have to remove the engine to redo all the plumbing to and from the turbos, and that would cost way more than fixing them, plus the engine would run terribly...
Sorry, but get it fixed or get rid of it.
Jim