You won’t do the work to back your own claim? Ok, well add me to the list of people calling bullshit then. Besides, who, but s cannibal would know the different between a leg of veal pork, and a... leg? Occam’s Razor says the books are jokes, pranks, or scams, and/or that you’re bullshitting. In the absence of evidence at least.
Well for starters you can try checking the watchpeopledie subreddit and look for human stew.
I don’t work for free, I’m barely giving a fuck away.
If you can’t back up an extraordinary claim, and “lots of cookbooks for cannibals” is pretty extraordinary, don’t make claims. If you don’t give a duck, are lazy, whatever, don’t waste your time making claims. It’s really simple, unless you’re wasting everyone’s time for amusement, and there’s a name for that.