Having found myself trained in the effects of starvation and. more critically, denial of liquid, the most even a fit person can last for is 48 hours - so solo mummification for three days is, like it or not, a recipe for permanent mummification. You cannot control the body's need to pee, and even though that can be recycled a couple of times, it soon becaomes poisonous. Dehydration is a true killer: it strains the liver into poisoning the body.
And that. sadly, is why I lost faith in this story inside of the first page.