I’ve used the same protocol and had good success for a broad range of C. elegans strains and for a whole bunch of species across several clades. It’s a pretty gentle version of bleaching (less sodium hydroxide than some), which means it can take a bit longer to fully dissolve the worms but may improve viability. One small adjustment, especially for some species: I sometimes pellet the worms and eggs long before the carcasses are fully dissolved, aspirate the supernatant, and add fresh bleach solution. I sometimes even do that a couple of times. It seems to help dissolve the carcasses fully, without killing the eggs.