Chuck Bumgardner has pointed out to me that Merz’s volume is available free online. Here is the bib data and link:
Merz, Annette. Die fiktive Selbstauslegung des Paulus: intertextuelle Studien zur Intention und Rezeption der Pastoralbriefe. Novum Testamentum et Orbis Antiquus 52. Göttingen: Vandenhoeck & Ruprecht, 2004. https://digi20.digitale-sammlungen.de/de/fs1/object/display/bsb00044367_00001.html
It appears some other German monographs are similarly available but our links aren’t working yet. If we can get good links I will post them as well.