Die Geheimnisse Der Bünzliritter [The Secrets Of The Bünzli Knights]

We discovered a cave in our building. If we believe Thomas Stauffacher, a descendant of the 1st Bünzliritter, the secrets of the Bünzliritter are hidden somewhere there. With the help of the Mayas, they have covered their tracks very well. We didn't find anything except the entrance to the cave. Can you interpret the clues correctly and find the hidden secrets of Switzerland? [ Bünzli ], the masculine, noundesignation for a Swiss, small-minded person, a philistine PS : we are kidding ourselves with the Bünzli :)