There were reports (claims I suppose) that the fsb were using telegram to organise the stochastic gig job sabotage across Europe
No no, reports: https://www.msn.com/en-in/news/world/russia-uses-telegram-to-recruit-spies-and-saboteurs-in-europe/ar-AA1xshqO
Does what has been found here shed any more light on that?
Not really/not directly, I would say. What you are describing is FSB using Telegram for recruitment. That does not require network-level observability and surveillance. That's a different "feature", so to speak.