Looking at the link from Thunder, it looks good if they can also have voice communication. Then if something isn't right, they can say, and the experts helping them can sort it out. Hand signals are likely to be a problem in the conditions they'll be in.
I'm not expert, but I think it's fair to...
I think there's a lot we don't know yet. One issue with waiting it out is whether the area they're in is safe, or if that could flood too.
The whole journey to the cave entrance isn't underwater, so the diving would be in stages. A monumentally difficult dive, but for someone being led it would...
The first 30 mins will be getting to know these wonderful kids, as they go on an adventure. The black screen bit for the next hour is a bit of an issue. I don't know how long they kept their torches going, presumably a flick of light every now and then.
All-nighter? Might take a bit longer than...