Not the OP, but this was a theme in the European Parliament in 2022 [1][2] and it was the object of a document that Greenpeace made [3] showing how pervasive the Russian lobby was over climate policies.
I personally do not believe that Russia does it in Germany via the Green Party but more so over other parties, such as AfD and BSW.
You can use the green party simply by donating sums to or amplifying extreme voices.
You do not need to control the whole of a ideology driven organisation , when you can nudge the extremists and usefools to undo their own organisation .
The party leadership forwards public transport, the oil lobby finances damaging cars, glueing to streets and other activities. The fanatics of your own site, are the worst enemy .
I personally do not believe that Russia does it in Germany via the Green Party but more so over other parties, such as AfD and BSW.
[1] - https://www.europarl.europa.eu/doceo/document/P-9-2022-00127....
[2] - https://www.europarl.europa.eu/doceo/document/P-9-2022-00127....
[3] - https://www.greenpeace.de/publikationen/20220517-greenpeace-....