I'm with Colliam. I assume they planned this, and a dive to 200 feet for 20 minutes or so would entail somewhere in the neighborhood of 40 minutes of deco between 70 feet and the surface, and that's assuming the deco is being done on 50%. So going to the surface from 50 feet would be blowing off a very large amount of decompression. If it happened to me, I think I would try to return to the water and do the omitted deco, assuming I was asymptomatic on the surface.
Bags of any kind are a hazard, and it's really important to have good and consistent and careful technique in shooting them. There is a thread here on SB recounting the story of Rick Inman getting the clip from his long hose caught in the line from his lift bag, and getting a ride to the surface. It happens. And this is also a very good argument for not spending your buddy's bag shoot futzing with your camera or watching your underwater video gadget or anything else -- when someone is doing something, whether it's shooting a bag or switching gases or moving bottles, the buddy should be watching carefully and thinking about what the likely problems are, and what the signs of something about to go wrong would be. This is one of the reasons I DO like doing deco in a horizontal position, because if I got caught in my bag line, I could kick toward my buddy and he's in a position to move instantly toward me.
And just because I'm a physician and a bit anal, it's not a pulmonary embolism we're talking about as a possibility here. Pulmonary emboli are clots or bubbles in the lungs; what kills people from rapid ascents is air embolism, which is air in the arteries that goes to the brain or spinal cord. This patient might have had chokes, which is a form of DCS where the bubbles in the pulmonary circulation overwhelm the lung's ability to filter them, but that still isn't termed pulmonary embolism.