It has happened at least once before with the big bore guns. Several years ago a woman was trying to shoot her boyfriends gun and she ended up shooting herself in the head. These guns recoil violently and some try to re-grip the gun as it jumps, and end up pulling the trigger again.
There are plenty of on line vids of folks (mostly women) losing control of 44 mags and such when shooting them.
Obviously, the woman was shooting the wrong gun for her or wasn’t holding it correctly. Also, apparently the range wasn’t clear.
However it happened, it’s a tragedy as she will have to live with this for the rest of her life, as will the victim’s family.
This is why, when I train people, if the gun has significant recoil, I only give them ONE cartridge in the gun until I'm confident they can handle recoil.
And start them out on .38 before moving up.