and all those 20000 chips are guaranteed to work?
i don't know about the failure rate, but i can safely assume not all of the 20000 will be failure-free....i think.
It all depends on the contract, was it for X Working Devices to spec Y, or was it just X Devices with a penalty for excessive defects beyond a certain percentage? We don't know, but it really does not matter.
They have stated "This is enough for the pre-orders and then some", this means that even if there are faulty ASIC's they should have enough for the current orders.