Regular warnings - IANAD, etc etc.
I'm fairly certain from reading raw test results and uncollated reports that the muscle burning thing:
A: isn't binary, you don't burn muscle and not fat.
B: is exaggerated among many 'westerners' due to the higher levels of protein and 'inefficient' muscle mass we have in general
C: isn't actually a big deal in active starvation scenarios. You may lose some muscle mass, but nothing compared to fat reserve burning. Many of the reports on muscle mass loss don't include active starvation scenarios
One thing that causes discrepencies is that people who report on data often fall into binary modes of communication, and end up communicating a "muscle OR fat" instead of "x% muscle and y% fat" result.
Another is that in general, fat cells never go away. They shrink, they empty out their stores, they sometimes do die, but they aren't really designed to be 'lost', just to give up the stored fuel. You can easily drop 60% of your stored fat by weight and lose almost NO fat cells.
The body is actually NOT designed to store up fat at the expense of muscle in a starvation scenario, it's actually the opposite. The body WILL try to find the optimum amount of muscle for the requirements of the lifestyle, though. In fasting diets and when people go full on paleolithic and cut consumption for the first couple weeks to cleanse, you find a lot of this happens. Everything from excess callous and digestive activity to muscle mass. The body is trying to become more efficient.
One thing I would propose to look at is to see exactly how much forage there really is. And don't get psyched out- a serving of meat is just a couple ounces, the average diner steak dinner is closer to 3 complete servings of meat. Similar goes for grains and carbohydrate heavy tubers and fruits. You can, pretty much, not counting dressings and condiments, eat as much dark leafy greens as you can handle and not suffer any negative effects.
I'd consider also modifying to include a children's chewable vitamin every day. My reasoning is that in a wilderness forage situation, you will have a greater variety of food that you probably are getting now. It sounds strange, but can be very true. Around here on days where I have experimented with forage only eating I find I eat well over a dozen different species of things compared to an average day like today with onion soup, a bit of salami, 3 sugar cookies, and eggs. So the children's chewable might increase your accuracy of results, in addition to helping you maintain energy levels.
I've also done 2 week lemonade fasts and rode over 30 miles per day on a bike, there's nothing wrong with physical exercise
And now I'm about due for another one.