What amazes me, is how the guides only need to be Full Cave certified to lead OW divers on these types of dives, personally, I feel it should be only cave instructors leading these dives, as they are trained to handle just about anything that may arise. Being certified Full Cave (and even an AOWSI), I am trained to solve many problems that can occur in a cave environment to get myself & my buddy (of equal or higher level than myself) out of a cave alive. We are equally aware of the risks we are taking. I realize that I am in no way qualified to handle a possibly panicked diver in that environment to bring them (& myself) out safely. When things go wrong, it is rarely only 1 thing, it is usually a cascading series of events that leads to a fatal event. Think of this scenario (I am in no way saying that this was what happened): Guided diver suddenly panics (remember when panic sets in, the diver most likely can only function in a survival mode, all higher functions are out the window) & tries to bolt in any direction, including up. They then spit their regulator out & put a fin in the silt. Now vis has gone from air clear to 0 in seconds. Where's the line? Now the nasty Halocline in that system isn't helping finding that line. Where is the other diver(s) being lead? Can I (as the guide) get them to the line & safely out? I can easily see where someone who isn't a cave instructor can quickly get overwhelmed by the situation.
Don't get me wrong,... I am sure there are excellent guides who are not cave instructors & have exemplary safety records, but is there a program there to teach these guides to handle those situations? Just putting in an observation.