I'm not sure if the pork rinds are real, but I'll tell you what real pork rinds are.
You get hunks of pig fat and you cut it up into cubes. Then you cook it for a long time and some of the fat will liquify. This liquid fat is rendered lard. Once you're done with that, you'll be left with cooked pieces of pig fat, and if you eat them they're really greasy. These are "cracklings", and when you put these in the oven and bake them, the grease drains out and they get crispy. Then you have a pork rind.
So the protein would just be from small amounts of meat that happened to be attached to the fat. If it's real, it will be cooked a lot, so I don't think it would be a great source.
