We can be sure that russain diplomat are all spies. Any Russian embacy is their layer. Agents, recruiters are almost intangible. Assassination of Rheinmetall CEO was prevented with US help. Mined DHL parcels. Power cables sabotaged. Car vandalism in Germany most likely was russian plan, trying to shift the blame at Green Party before elections. And don't forget russia in possession of most dangerous neurotoxins in the world.
Would EU secret services cope with all of that? Even if US abandona it?