TODAY'S SUBJECT:  Ignatov walks:  why?

Would someone please tell me why it is Ignatov gets to walk after fingering Q for the KGB?  Apparently, here's the way it goes down:  Q's tracking Ignatov, after having been given his name by Natalya.  Ignatov, on instructions from Schrenk, leads Q into a setup where he makes a call to the KGB, goes over to a militiaman, flashes his Party membership documents and Kremlin chauffeur authorization, and waits until Auntie KG tries to close in on Our Fave Ferret.  Now, if we're to believe what Schrenk says later, Ignatov got the authorities there by telling them Q was Helmut Schrenk.

Yeah, very funny, a little of what Dr. Lecter might call "asylum humor." They chuck Q into Lubyanka posthaste, learning quickly he's *not* Schrenk, that in fact he's probably an agent whose "shoes" aren't so good.  Then, irony of ironies, they ask Q if *he* knows where Schrenk is!

But here's my problem; later, when Q escapes, killing Vader and some other guys, why don't the KGB make a beeline for Ignatov?  It's odd enough they don't go after him the minute they learn Q's not Schrenk; I mean, he can't go to ground without relinquishing access to the all-important Zil limousine, so wouldn't you think they'd try to pick up the clearest trail from the last time they lost it?  Ignatov's go some blat, true, but not all that much ("nothing else in the way of privilege documents," Q sniffs, going through Ignatov's wallet, "but that one would probably rate a salute from a militiaman, yes" [13:29]).  This is Moscow, remember, where an army of KGB agents operates.  How difficult would it have been to put a routine tag--not even a whole group, just a couple of agents--on Schrenk to see where he went?  That way, they would have gotten not only Schrenk, but Quiller as well.