I dont have any experience with procomp shocks, but that mounting style doesnt look right
I think the mount looks correct for a rear JK shock. Looks like the bushing just slipped out of the bore at the end of the shock shaft. You can probably remove the shock and use a little soapy water to push the bushing back into the bore. That said, I'd be curious as to why it came out in the first place. Is it possible you over compressed the shock. Meaning, your bumpstop isn't tall enough and the shock is actually what stopped the up travel of the axle.
I just looked it up, and i think your right. Im used to seeing the top mount in the rear having the ear tabs and not the thru hole.
And im with ERAUgrad, curious to why it pushed out as they should be pretty tight.
Did that change on a certain year model?