I don’t know about Wagner or Russian killed/wounded statistics. I have watched unough combat medicine and field hospital video made by Ukranians that I have formed an opinion about the Ukraine soldiers. They and the medical staff do their best to keep spirits up, making jokes or expressing concern. A number have expressed the wish to get well and return to their units as quickly as possible. Perhaps there is some of that among the Wagners, but I very much doubt it exists to any degree among the Russian military. Some Ukraine soldiers mentioned being wounded several times, but rejoining their units with enthusiasm.
Ukrainians are fighting for Freedom, Family and Country.
These are the three basic elements necessary for a working, civilized society.
It gives Ukrainians an indestructible sense of righfulness. A moral high ground, something the Kremlin deep-staters are in complete lack of.