We don't have much information about this skydive because the video was submitted with minimal comment from the student, who was at a non-US dropzone. (We don't know if it was a USPA affiliate.) This was described as a AFF "Level 6 jump." In short, the student went into a flat spin and the instructor attempted to stop it but largely failed. They then lost control of the student, the instructor sunk out, and watched the student deploy from a hundred feet away. The student reported some line twists but landed safely. Sadly, the incident caused the student to quit skydiving, they stated, "It's too dangerous (maybe I'll go to the wind tunnel)..."
Again, we have minimal information on this jump, but suffice to say that this whole incident appears to have happened due to a instructor who either didn't have the confidence, or the ability, to get in there and stop a rotation that rapidly put their student into the spin cycle. Admittedly, once a student starts spinning, staying on level — let alone get in there and stop the spin — becomes much harder. However, the video is deeply suggestive of an issue with the instruction here.
First, while we know that sometimes a great student suddenly has a brain fart, this jumper does not look like they had the control requisite to pass their Cat C jump. Further, while — yes — the instructor initially attempted to stop the spin, it needs to be noted is that, as one experienced AFF-I put it, "The student never earned the right to be released after that. The instructor should have held on until the student corrected the body position before being released."
We normally love to crack jokes and add some light humor into Friday Freakout, but this is a particularly rough video, and it sadly made someone think that a sport dedicated to safety, is too dangerous for them. The first way this could have been prevented was by the jumper having not been cleared for this level of AFF jump. Further, if this instructor wasn't capable of handling this type of instruction, they shouldn't have been allowed to take a student up. No student should be allowed to go up into the air with an instructor who is incapable of assessing the need for them to intervene in a flat spin and then making that intervention. Lastly, if you know your student is of a body size you cannot fly with, you should have good enough judgment to have someone else take them up.