The responsibility to make good hits & clean kills lies with the shooter, if he can't handle the gun/recoil then he needs to go to something smaller or wind his loads down. You can't kill what you can't hit & this might sound like a broken record but a shot in the dirt doesn't impress any animal, whether it's a lion, a cape buffalo or a ground hog.
You have control over what you shoot, if your buddy is shooting a big gun & you can't handle the recoil you've got to make some changes. Very few of us would choose a 10mm for cape buffalo or a 9mm for brown bear but accuracy & penetration can make up for a lot of wasted horsepower.Which is worse being over gunned & missing or being under gunned & placing your hits?

Dick