I know you've already added a note saying the article is just a bit of silly inspiration, it's worth mentioning that consensus research from more sober sources seems to indicate that the real-world purpose of the NKVD's "Special Department" was the creation and maintenance of the Soviet Union's system of concentration camps for political dissidents - Solzhenitsyn actually refers to Gleb Bokii as one of the three leaders of this department.
Which doesn't mean that you can't also use it to drive more fantastical, pulp-oriented stories in the same way Himmler and the Ahnerbe are also great sources to drive Nazi-occultist plots. Gleb Bokii (and the others mentioned in the article) was most definitely into mysticism and there's no reason he couldn't also use his broad authority to authorize special missions by NKVD agents to investigate mystical or occult events, people, or places. But some might find it a bit grim, unless perhaps (like most Nazi leagues) you're mainly using them as villains or otherwise acknowledging them as "bad guys". So just adding a bit of a disclaimer here!
I did however trip over this additional,
incredible line in the wiki article for Bokii:
Bokii's fellow bureaucratic NKVD foes had conjured up fictions of his being as a sort of Dracula-like human blood drinker.
So there's even more inspiration for you!