Still, something really annoys me: Your German Doctor. He's only a minor character with a few sentences but with these he managed to annoy me very much.
You made quite clear that Artemis would only fetch the best and most famous doctors to cure his mother. Doctors don't get famous by sitting at home and doing their everyday-duty. They have to attend conferences, hold speeches, diskuss with others, publish papers...whatever to make themselves a name. If they also want to be recognised internationally (and this guy obviously is, as Artemis knows about him) at least some of this must happen in English, so they have to know the language fairly well.
I have no problem with the fact that you wrote 'He had a heavy German accent'...everybody can have an accent, but that you made him say 'Is it why I from Germany comming that you do not understand me?'...seriously that really hurt. Even if you translate it word-by-word back into German the sentence doesn't make sence.
And even when you say 'This guy had all his works translated, always an interpreter with him at conferences...or whatever reason to give him a bad English, than at least do it constantly. Apart from this sentence all otheres were in proper English. That doesn't make sense.