Is it possible that the NO2b was wrongly listed under Hermann Klotz rather than Günther? Or that Günther also received it but it was lost in the shuffle and never gazetted?
Looking at that ribbon bar, although image quality is not that great on these old B&W pics, I don't see anything that fits the distinctive thin black edge stripes of Hermann Klotz's WK3. However, the last two ribbons look like they would fit Günther's SA3a and HP3a. And as commander of a Hesse regiment, a Hesse General Honor Decoration for Bravery would fit the second spot after the Iron Cross 2nd Class.
That would make the ribbon bar:
EK2 • HT • RAO4 • KO3 • DA • Cent • SA3a • HP3a
Which fits Günther Klotz's known and with the HT likely awards.