That predator bass’s mouth looked a little sore there.
I have a hard time believing that one was actually trying to eat that other one. If it isn’t fake, then the one in the mouth must have been charging the other one when it was opening it’s mouth to get wedged and hung up on the gill plate.
About 8 years ago I came across the same thing but it was a 2# bass in a 3# pikes mouth. I tried to pick them up in a net and I knocked them loose. Craziest thing I ever seen on the water. I laughed my butt off thinking about these two fish staring down each other waiting for one to make the first move.
It also makes you wonder how often does it occur where a fish eats an unusually large prey. We wouldn’t see it because the fish is probably going to lay low and digest the prey a few days, or however long it takes, before chasing a lure.