Like I said, people who know how to ship fish usually have them arrive alive even when delayed some. And good sjippers always make good on DOAs. The problem is often on the buyers end because the cost of shipping fast is not cheap. So as buyers we find it hard to buy say $200 worth of fish and then have to pay over $100 to get them overnight. My rule of thumb has always been, "Fill the box!" when you order fish shipped.
The fastest way to have fish shipped is airport to airport. I used to do that. I would arrange for flights to arrive about 10-11 pm. I did this because the drive from where I live to NYC airports during most hours is up to 2 hours each way, At that time of night I do it in about 40 minutes. This shipping methids is also usually the least expensive. However, since the problem with terrorism loomed, one needs to register with the airlines to drop and usually to pick-upget shipments. That didn't apply when I was doing this. Also, Covid has put a dent in the number of flights as well as the excess space available in cargo holds,. So this is a consideration these days. It has also affected all of the other potential shippers as well.