The BBC calls it Nazi archeologists which is still not really correct or fair. The Nazis were a political party, not everyone adhered to it's views. The archeologists might well have been on the other side of the political spectrum but had not much chance to change country. It's like calling all Americans today Trump cashiers, Trump archeologists or Trump teachers. Doesn't make sense.
The SS was much more than a military group. It was a weird mix of paramilitary organization, police force, academy of sciences, academy of arts, men's club, cult, and think tank.
Except they did. The project that led to the Lion Man was started by paleontologist Robert Wetzel who joined the SS in 1937 and later became Sturmbannführer.
Völzing's excavation was funded by the SS which was not something that you happened to be roped into without your knowledge.