When the author describes the history of the feud between the two families, he notes that Georg and Ulrich wish misfortune on one another. They have continued this inherited feud simply out of tradition and out of a continued personal ill will for one another. But it would be an exaggeration (hyperbole) to say that "they had thirsted for one another's blood." It is possible that their mutual hatred is so great that Georg and Ulrich both wish each other dead, but that does not mean they have an actual cannibalistic thirst for human blood.
After they become trapped, Ulrich says his men are close behind and will arrive first. Georg says the same thing. Both men are being hyperbolic. Neither Georg nor Ulrich know how long it will be until either party reaches them:
Both men spoke with the bitterness of possible defeat before them, for each knew that it might be long before his men would seek him out or find him; it was a bare matter of chance which party would arrive first on the scene.
When Ulrich manages to get a drink of wine, it is described as a "heaven-sent draft." It only seems this good because he is in such a dire predicament and it serves to calm his nerves. Their reconciliation is "dramatic" but this is a fitting description and not really an exaggeration.