My suspension of disbelief died when the document suggested naturally occuring ramjet propulsion bovines. That's all I wanted to say, but when I went back to review some details, I found even more ludicrous claims.
The document refers to a maximum recorded speed of about 4 km/s, resulting in a subject fatality after sudden deceleration. This is around 4 times higher than the current maximum recorded aircraft speeds (MiG-25, SR-71 Blackbird, others), noting that at those speeds the mentioned aircraft come dangerously close to disintegration. The subject skeleton has less toughness and more tensile strength than B. Africanus bones, resulting in an extremely brittle structure unable to perform on a level remotely similar to a proper aircraft frame.
A glance at the redacted information regarding maximum bladder pressure suggests an order of magnitude of 10^3 MPa. Another glance at maximum pressures for industrial high-pressure gas cylinders results in a value of about 4000 psi. This makes the subject's bladder around 100 times more resistant to pressure than the best industrial cylinders.
Suborbital flight is a complicated issue regarding the scramjet variant, because even scramjets require an air intake, and suborbital flight is done outside the atmosphere. Still… given that this flight is mentored as "limited", I'll give it the benefit of doubt.
Same feelings regarding the subject's capability to withstand the extreme temperatures resulting from these propulsion systems. It is almost compete nonsense, given that the best titanium alloys have a hard time with them. The mucus ideia is interesting, and it could even work in specific circumstances… however, the ablation rate from the exhaust gasses would lead to a severe reduction in subject mass, or insufficient mucus production.
The whole spiel about anally-released superheated "flatus" and the last addendum's reference to the "cow jumped over the moon" trope really are just adding insult to injury, though.
I think this is a prime example of why the "a bad idea can be made great with good execution" mantra is just flawed. Supersonic fart cows. At the end of the day, it's what it is.