Trillions is a ridiculous claim. Billions $ easily, budgets of GRU and FSB during last 11 years of war against the west have ballooned.
The situation is, people don't need billion dollar bribes. In my backwardish central european country they caught one government official who was physically handing over state secret material to a russian spy, straight from their embassy, for 500 euros a pop. There is a a video record with good audio from that, the conversation is really absurd yet real. You just need to find one gambling or alcohol addict, or some other failures and press few buttons.
Also, for russia undermining literally whole western world is mission with priority #1 for last 20 years. Eastern european countries who intimately know how bad russian terror actually is were warning about this repeatedly whole western world, to be very effectively ignored and laughed at by western leaders till SHTF.
Sure, those were not plans for F-35 or new aircraft carrier but people take surprisingly little to get corrupted, some even do it for free for ideological purposes.
They willingly settled for $1B with the FCC over Uzbekistan. Over Uzbekistan. It has to be insignificant money for them, otherwise... they would have simply not paid.