Well the latest information on DR1 News is that you can't get a test certificate you can come anyway and have you temperature taken on arrival. My guess is that there may be a delay for those without certificates.
Well I think I will still get tested anyway before going and carry a letter from my doctors office just in case. But it seems to be that there have been a few new posts today on DR1 in another forum saying that it won’t be required unless the passenger temperature upon arrival Is above 38degrees, and if so then they will be tested at the airport. Don’t quote me though. I’m waiting to see when someone on here actually arrives in RD on a flight and posts what their experience was upon arrival.