I haven't had a chance to see "das Finale", but I believe this is referencing some scene where Sodoko's tank gets stuck in some muddy river and she has to help get it out.

HawkeyeNFO said:

I haven't had a chance to see "das Finale", but I believe this is referencing some scene where Sodoko's tank gets stuck in some muddy river and she has to help get it out.

Yeah, it's in Das Finale Episode 2 around the 38 minute mark.