If i understand the Troika right, then Greece is currently doing everything to violate the bailout treaty. This creates a legal situation where Greece will be complimented out of the Eurozone.
For your question: Greece will go first. Germany will follow out only if true fiscal union can not be achieved. This may also happen if Greece was out first.
Pricetag for Germany leaving: 1,2 Trillion immediately plus economic downturn for some 5 years, but structural imbalances in the Eurozone solved for all others.
Pricetag for Eurozone to kick out Greece: Some 350 Billion plus no structural problem whatsoever solved.