This site appears to be for return flight testing only. As
@lexvil referenced below your post, the third day antigen testing is arranged when you fill out the app that Curaçao requires. According to one of the preferred labs website (Lab de Med,
www.labdemed.org ) this test will cost $35 per person. Also, that particular lab will come to your location free of charge. Again, I’m no expert, and this is all based on their website.
The other thing I noticed about the prices you used is that they are for concierge service, so no cost of travel for you and no real loss of dive day. The testing cost if you go to them for the PCR is $115 vs the $179 for concierge. Now, not losing the dive day might be worth it, but you’ll need to decide about the cost of travel. I’m assuming you’re flying Delta, since the website is done in conjunction with them, so they may prefer you use that lab for return testing but you may want to check the website
@lexvil links in his post.
Erik