Why it puts in sitemap REVISION-v1? It leads to 404

Did you try re-saving your permalinks settings per the FAQ section? Worked for me.

Though I still can’t find where these files actually exist in my directories..?

Let me clarify a bit:

https://www.raumline.ru/2015/06/976-revision-v1/140964576372_full/

It generates links to revisions, like this.

Why permalinks should be involved in this process?
Revisions are totally internal thing for authors.

Tried to fix it with robots.txt, but seems it is defineteli the bug…