Originally Posted by TreeSemdyZee

You might try Leatherique Pristine Clean. I can't swear to you that it will clean deodorant out, but I've used it a couple of times including on seats that were about 15 years old. You'd be amazed what kind of crud this stuff takes out.
The Leatherique Rejuvenator Oil also does a real nice job of conditioning of the leather.
Since the deodorant has probably taken a lot of the oil and moisture out of the leather, the Rejuvenator Oil would most likely help the situation. If you use this stuff, you need warm weather. I left mine on the seats for 24 hours+ with plastic over the seats, then came back with the Pristine Clean. The P.C. brings the leather back to the same matte finish as original.