You already contacted the source, that is job one.
Asking fellow hobbyist about their experience I can only share mine. Two part answer. The first is that it will depend on how the animals are packed. If done properly the chance of arriving alive increase. The second part is out of their control and how the package is handled and its holding area. This is the higher risk area.
My experience is as follows. I ordered a Pyramid and Zoster butterflyfish from Divers Den. It was supposed to arrive overnight but was delayed at the local sorting facility. I made contact with LA/DD to let them know and see if there was anything they could do or recommend. They responded immediately (it helps that this was early in the week, not Friday) and said to accept the package regardless and to follow up. They reaffirmed that the packaged should be able to handle another 24 hours due to the size of the box, fish, and water used. I took them at their word.
Long story short, package was lost at the sorting facility and I did not receive the package until the 76 hour mark. Per LA/DD's recommendation I took in the package, snapped some photos per their request, shut off the lights in the room, opened the box. Both bags had lower half black, upper was clear. I had to tilt the back to see. Pyramid was looking right at me like what the heck, get me out of here. The Zoster was on its side. Not ideal, nor recommended, I floated the bag to bring up to temp, opened it, and moved the Pyramid to the display with lights off. The Zoster similar but placed it in the refugium. Pyramid went behind the reef structure, Zoster to the bottom on its side. I put some gloves on, collected it, and gently moved it from side to side because I did not know what else to do thinking maybe movement would help.
Anyway next morning lights came on in normal schedule and the Pyramid was out and about doing butterfly things. Much to my surprise the Zoster was out too asking to have more space and food. Both are doing fine 7 years later which I guess is the moral of my long winded post.
Packaging makes the difference as to the location/area of the package. Mine lasted over 72 hours and came out ok. I would not recommend this, but LA/DD packaged very well and was great to work with thought it all....