That's going to depend. Generally, if there's enough proof to prove a transaction did indeed happen, and you have proof of your more substantial claims, it'll go through. But we won't just accept a pure text post going 'This person did a thing', you know? We do need something.

So it's case by case basis. We won't know until we see the post itself. Posts have to be manually approved so feel free to write one up (though it might be better to wait to see if he does pay you, but that's up to you), and if there are problems, you'll receive a rejection notice to the email you have your LJ account attached to.

(Also, as an aside, in regards to your first comment, please don't edit your posts to remove information!)