The shooter's sandwich you linked involves cooked mushrooms and fried steaks. In contemporary food safety practice, this is not shelf-stable at all. It can be held 3-5 days in the fridge, or up to 2 hours at room temperature.
I can imagine that hunters did take it on longer trips historically. They lived in a time when mild food poisoning (symptoms limited to bloating and light diarrhoe) was commonplace, and the average person experienced it as often as the common cold, if not a bit more frequently. More serious types of foodborne illness were less frequent, but still appeared with some regularity in a given population.
There are two reasons we don't eat this way today. First, our standard of living is higher. We have the possibility to drastically reduce our risk of food-borne illness by choosing nutritious shelf-stable food for situations we need it, and we have much higher expectations of our own quality of life, including the expectation that the chance of getting bloating from a sandwich should be close to zero, not close to 10%. Second, our meat today well may have much more pathogen contamination than in the past. If you slaughter one healthy animal in your small farm, the worst you get spread over the meat are some E. coli from inside its own guts, and normal E. coli don't cause too bad symptoms (mutations can be very dangerous, but they are also exceedingly rare). Today, animals are penned together by the thousands, exchanging exotic pathogens while still alive, and then are slaughtered and eviscerated in efficient conveyor-like manner, so that if one cow had some unpleasant bacteria from somewhere, they will probably cross-contaminate the steaks from hundreds of other cows slaughtered in the same shift.
Bottom line: It is absolutely not safe. You are free to decide to take the risk and eat it, but by the usual standards in the food industry, this is an unacceptably high risk, and it is foolish to take it.
Best Answer
Basically once cooked and if stored in a dry container cookies will keep for a couple of weeks at room temperature and several months (perhaps a year) in the freezer.
The biggest problem with these cookies will be degradation of the fats in the almonds and butter resulting in rancid tastes - these are not dangerous, just unpleasant.
There are few risks with food safety regarding cooked cookies as the temperature of cooking is enough to kill all potential pathogens and typically lowers the water activity within the cookie to a point where few pathogens are capable of growing. It is hard to say what the exact water activity of your cookies will be, but I suspect fairly low.