Another thing Khashoggi's murder highlights: it's becoming increasingly difficult for intelligence services to hide the identifies and activities of their operatives. Competent researchers can much more easily map them out by accessing social media, CCTV data, public government databases and the occasional leak.
Mossad, alternatively: https://en.m.wikipedia.org/wiki/Assassination_of_Mahmoud_Al-... — although the victim was far from either a dissident or turncoat.
I struggle to believe the author wrote this with a straight face. Are these the same reliable intelligence services that just help purged half the Army officer corps, Judiciary and Turkey's teachers because they are conspiring with a religious leader in the USA?  I am quite sure they would point fingers at whoever Erdogan wanted a finger pointed at.
I don't know the politics going on behind the scenes here, but I do not believe anything either side are saying.
I wish the USA could convincingly say something to the Saudis, but with our recent surrender of the moral high ground (and indeed increasingly convincing speculation that we armed the Saudis with intelligence that informed this purge), that is probably not going to happen.