Bruised shoulder or collar bone.......sure. Broken in normal circumstance? I doubt it.

Whenever I let someone not accustomed to a big rifle try any of mine I will always admonish them to:
“keep their nose away from their thumb, pull it hard back into their shoulder, and grip it like they mean it”.
That and I load only 1 round in a double.

Have had smallish men and 5’ 5” women try them (NOT on a bench of course) and never have had one lose total control of the rifle.
A step back, spun partly sideways, barrels pointed 40° up at the sky.......but never lose grip and get clonked in the face, or actually drop it.

I, or one of my big bore shooter buddies, will stand at their side and slightly behind at the ready to catch the rifle .......just in case.

-Mike