Actually Bish, there was fighting in Warsaw in 1944, in which the Fallschirm-Panzer-Division HG was involved. In the fighting at the Weichsel Bend on Aug 3 1944, the III Soviet tank corps were defeated. Generaloberst Model stated in orders that it was thanks to the efforts of F-P-D HG that Warsaw could be held one more time.
I could find nothing about the Sdkz 215/22.
My references are from "The HG Panzer Division" by Alfred Otte published by Schiffer Military.