Chelsea make stupid, short term decisions all the time. That's almost the basis that the club is run on.
If it was a soundly run, well structured club with long term planning, I'd agree that we've got little or no chance. But it's Chelsea.
Also we wouldn't be in talks unless Zouma was 100% clear he wants to stay (which is also a big factor that people are ignoring).
I think Big Marcel will get him, unless the price is too prohibitive.