Rupert has balls

I don't think this is good writing or anything. As you point out, it's kind of terrible. However, I think the author's main point is correct. Rupert just makes it up as he goes along. There is no grand plan with his Google stand-off. It's like a poker semi-bluff, he can go with it because any outcome is acceptable.

I don't know if it's how the phrase was originally intended, but it makes a lot more sense to me if I read it as "until the value of his experience expired."

I don't think "experience" in general could possibly expire (it's just another word for "knowledge", after all!), but certainly individual experiences can become irrelevant.