Dang man sorry to hear. That was a beautiful fish.Honestly a lot of the "easier" butterflies seem to arrive in worse shape. I think less care is put into every aspect of collection and transport since they are not worth as much.
I actually lost the saddleback as well 2 days ago. Atrophy of the kidneys and retention of bright coloration more than 24 hrs after death (which leads me to the conclusion it was cyanide collected). It lasted roughly 22 days, which fits well with the timeline for a cyanide collected fish that was transshipped and did not sit at a wholesaler.
You’re probably right about less care put in as there cheaper. So sad there suck amazing fish.