Well, the first and most obvious question is whether or not you can read German, because most of what's been translated into English comes from foreign language newspapers that would rather avoid the issue of victory altogether.

Generally speaking though, one of the major problems for Germany was the question of what "victory" even meant: while the idea of defeat was "unthinkable," especially with the police looking over everyone's shoulder, Germany was a rather bizarre mixture of believing itself the victim in the war, and expecting to make material gains.

As such, depending on who you asked, ending the war without war reparations or territory losses could be a "victory," as could annexing most of Eastern Europe. Few would disagree with the former (at least openly,) but how many genuinely expected the latter before Russia's collapse is a much more open question.

After Russia's collapse, most people would have likely expected to keep the territory gained, but that made Germany's subsequent reversal all the more shocking, and presumably despairing, since the German government was clearly more afraid of ending up like the Tsar than admitting defeat by the end.