A Turkish officer absolutely could be awarded a Prussian order. For example, Enver Pasha received the Pour le Merite in 1915 for his part in the Gallipoli campaign. As i understand it, the Red Eagle Order was the usual peacetime award to foreigners. Early on, there was a special version for non-Christians but, it was short lived and the standard version was awarded in most cases.
I haven't seen enough Jerusalem crosses to have an opinion on that but, the Anhalt piece appears to be silver-gilt, which is a bit of a red flag for me. These are generally bronze-gilt like the Albert the Bear awards.
The Princely Hohenzollern grades were a bit different than the usual setup. The pinback cross, usually an Officer's Cross in many orders, is actually the 1st Class for this Order. It grades below the Grand Cross but above the Commander's Cross. It was awarded 561 times from 1852 to 1965.
Just a comment - The 1870 bar combination is a bit unusual as the large units that were at Orleans were not at Weissenburg. It could be a staff officer or someone in a position that called for him to move around between units but, it is a bit of a red flag.
FWIW, my understanding is that the only wartime jeweler for these was Bernard Knauer. They used the mark "B. KNAUER" up to the early '20's, usually on the underside of the pin. The mark was changed to simply "KNAUER" sometime in the early '20's. Although marks can easily be reproduced, I understand that pieces marked only "KNAUER" without the "B" are, at best, 1920's or 1930's replacements.
Raising this old topic, I recently got this pair as part of a larger lot. I thought I would get your opinions. They are the Frankfurt Medal for 1814 (est. in 1846) and the Frankfurt Medal for 1815 (est. in 1816). Both are beautifully struck and are the correct weight. Any opinions would be appreciated as I haven't seen enough of these to develop a good feel yet.