Started reading this extra long post and got up to No. 191368106 and had to stop to present this objection re WWII not allowing enlistment / only conscription
My dad enlisted in the Navy during WWII, when he was 18 years old.
He said that it was common for guys to enlist in the navy rather than risking the chance of being drafted into the army. The army was considered to be more dangerous and more likely to be killed.
I did have a thought about Jews in concentration camps though.
I've often wondered if it was safer for an able bodied man of military age to be in a concentration camp than to be in the German military. Excluding the starvation factor that ensued when the allies bombed their supply lines.