This did not appear to be a pressure vessel failure, but some interconnecting hose failure, so a small explosive release of pressurized gas.
I just don't see CNG or compressed hydrogen in our future, I've seen it suggested in books back in the 1960s, but 4000PSI 270BAR, is not something that is safe to handle by common auto owners. And there is currently an accident rate in manufacturing plants, that if expanded production occurs, will be a common event.