We had our PCR done at CVS, start checking at 12:01 AM online to make appointments, they will get booked up and they do 3 day out appointments.. They also have urgent care that might be able to do your fit to fly..
Our Visa was a little different than yours we did the OA retirement but if they're requesting proof of payment then I would think yours has been approved
You fill out the application first online then you submit a itinerary for flight and possible asq once that is approved they will request your original documents you will send those in then they will approve those at that time you will submit your airline, asq, and insurance receipts then they will issue you a COE