Some of this was already in a 2017 study published by WADA.
One reason for excluding testosterone is because that is not a common drug among Kenyan athletes -- only 1 bust between 2004-2018.
Renato has explained before that Kenya sources its legitimate medicines from Asian countries where they are cheaper, but also quality control is less than Western standards. Furthermore, pharmacists remove the exact quantity of drugs from the bottle and give them in an unlabeled container, to stretch the medication further, but making due-diligence impossible.
No one has heard of Jordan Chipangama. He is a 2:11 runner from Zambia who ran in the US.
When WADA banned meldonium -- a common drug prescribed in Russia and Ethiopia -- it was controversial. It was apparently banned on the observation that a lot of athletes were using it, therefore they must know something that WADA didn't. (An argument that WADA rejected for thyroid medication.) The more conspiracy minded suggested it was a way to target Russian and Ethiopian athletes for busts, rather than ban a performance enhancing drug.
I'm also not as convinced as Renato about nandrolone. Nandrolone injection is a common treatment by doctors for muscle injury -- and the 2017 study reported that a lot of athletes and doctors are not aware of athletes obligations with respect to common treatments. Furthermore, we learned, at least in Kenya, farmers do not routinely castrate their pigs, so consumption of intact boar meat and organs leading to unknowing nandrolone ingestion would be more likely.