Something like this happened to one of my projects about two months ago; it was published and indexed, and even sold one copy, but a day later it was no longer searchable. I emailed support but never heard back, so I basically gave up. I just released a new project today that seems to have never been indexed at all. I've heard there is a review process for paid games, but I've never received any notifications one way or the other, outside of the "congrats you published a game" email.