The BND seems to have a continuous history since the 1990s of always having one high-ranking official that lateron turns out to be under strong suspicion of having spied for Russia.

Truth. Even Reinhardt Gehlen had this problem. That's why, if you're going to run Ops with Germans, at least imho and exp, you really have to run things TOTALLY compartmented. Seriously. OPSEC matters. The Purple Dragon. Learn it, do it, and you'll live. Best, HTM III