When I approve an expense report, why does it move to "In escrow"? Do I have to do anything else to pay Freelancers?

By approving the expense report, you are approving Cadre to queue up your Freelancers for payment and to release those funds. Once payment is completed, it will move to "Payment Complete". After approving the expense report, the only thing left to do is leave feedback for your Freelancers.