I listened and watched the documentary. And I am native german .
Here is what happened: Hajo Seppelt, journalist went to Kenya and claimed to be a European Athlete's manager. He spoke to one of the leading Athlete's doctor there about possibilities to get "extra support" = doping (this was videotaped with hidden camera). He was pointed towards the doctor from a source in kenya track and field.
The doctor went on and openly talked about opportunities to perform blood doping, where to hide the blood bags, etc.. He said he has already a lot of experience with this. He can also get HGH's if he needed and EPO. Doctor said he is working with a lot of athletes, from many countries including Bahrain and the US, but of course does not want to call names.
Journalist Seppelt asked about doping controls in Kenya and the doctor said there are not many controls in Kenya, also he has a program running where he regularly checks the urine and blood of his athletes to see whether they could be tested positive.
a) ARD is not just some mainstream media source in germany that focus on celebrities or so, it is instead historically a unbiased media program and to some extent comparable with the BBC.
b) Still I am a bit sceptical. This reporter guy was sort of exaggerating by saying this interview and the research he did gives him enough evidence to convinced that most kenyian athletes starting in London this year will be doped. He also repeatedly simplified the whole reason why kenyans are so good as simply stating "well, we always thought that it was only the altitude, whereas in fact I have now evidence it might be also due to doping".
I am not sure what to think of this, to be honest. By the way he did not make the claim Chelimo is under a doping program he only said that doctor showed him her blood profile.
hope that helps a bit.