I have twice responded to your message, but it does not appear that you are receiving my replies. Consequently, I'll post here.
Jan 11 11:28 AM GMT
I checked for Gruzalski but found no one by that name. I also checked on-line here at ancestry for that name in the 1870/71 casualty lists without success.
As for Lohrer et al., I did find a Friedrich Lauer listed as a private in Grenadier Regiment 3. Unfortunately, there is no way to determine if this is in fact your relative.
The commemorative medals were given to all who participated in the war or who entered "enemy territory" during a certain time period. It was widely awarded and was accompanied by a nice certificate.
If you have any questions, please let me know.