I believe the Captain did say it was blocked on the radio transmission, mayday call.
Jerry Boylan- Captain of the Conception is one of the best or he wouldn’t be working Truth Aquatics or Conception. I don’t know him personally but his reputation in the dive community is unquestioned. I’d go on a boat with Truth Aquatics tomorrow if they asked. People envy that kind of operation around here.
Regardless of how or what started the fire, it burned incredibly hot and spread quite fast with the main evac route blocked by fire.