The time tracking is to protect the client from the freelancer scamming. Time is not even being disputed here. Upwork is handling payments, and taking 20% fee f

The time tracking is to protect the client from the freelancer scamming. Time is not even being disputed here. Upwork is handling payments, and taking 20% fee for that risk (as I recall), so they need to eat it when they screw up by allowing payment with an unauthorized card. There is nothing the freelancer could do to know that payments are valid, because upwork is supposed to do that.