Another source I spoke to was "eaten alive by anxiety" over the investigation and baffled that Germany, a close ally of Ukraine, was even pursuing prosecution.

What's so baffling there? The act of building the pipeline showed where Germany stands, or rather bends over, in relation to Russia.

Poland is great about this though:

Last year, he was arrested in Warsaw on a warrant issued by Germany but a Polish judge refused to extradite him.

In a dramatic twist, he ruled instead that a Ukrainian attack on Nord Stream, if that was what happened, would be a "just" act in a "bloody and genocidal war".