Mannheim department is unhappy. ZEW people are unhappy and leaving like crazy (e.g. Steffen, Peichl, Hüschelrath).
And Wambach wants to hire is cronies with AL and CG that are clearly velow Mannheim standards (no top 5)- and all this despite several candidates with much better publication records (including top 5s) applied.
To be fair the ZEW professorships are not quite the same thing as the regular Mannheim professorships. Standards are clearly lower as the work is less attractive.
The question is whether they could have gotten someone who is better in terms of research potential and better suited for the work at the institute. These talents don't come together too frequently, so I think we should congratulate Mannheim / AW for their decision.