It was a typical Cozumel dive boat. They have easy access to a chamber, so there is normally no need for IWR. When she surfaced, she was already in trouble. Under the best of circumstances, the boat should have motored as fast as possible to a dock, radioing for an ambulance. She had been doing a super deep bounce dive (300 feet planned; 400 feet actual) with 2 friends. They jumped in about the same time as a group of divers doing a typical recreational dive. Their dive took little time, so they surfaced long before the regular dive group. That put the captain in a dilemma, because it is strictly forbidden for a boat to leave with its divers still in the water. (In a normal DCS case, the DCS occurs at the end of a dive, not the beginning.)
Please remember that this thread is not about that case, which was discussed at great length when it happened.