You report revenue and expenses during the quarter in which they were earned, not when they're paid. So a delay in payment wouldn't change their Q3 filings at all.

Beyond this, Google makes a profit from having both sides continue to participate. The more ads they can show, the better. Hampering one side of this equation for temporary gains that only really improve how you look to Wall Street (not how you're actually performing) is silly, and seems completely counter to how Google typically works.