Dangerous inspection
Learning about the realm above the fifth level was challenging. Only specific, wealthy parties had access to that kind of information, and even then, they mostly owned fragmented reports and studies.
The issue wasn't only a matter of monopoly over information. Humankind was very new to the evolution field, and few specialists could understand it. Adding the immense wealth and resources required by the procedure to the equation decreased the number of knowledgeable people even more.
Khan's unique procedure added another filter, reducing that number to zero. No one knew what he was doing or where his training sessions would lead. The scientists could only study him and adapt accordingly.