Mark, if you have the means to take the right lock plate off, you will be able to tell if the lifter is floating in and out of the cocking rod shaft fit.
I would tape the area around the screw and with the right size bit take the long connecting screw out on the left lock and then thread the screw into the right lock and gently pull it off using the screw.
Since this was just done it should come off fairly easy.
My guess is they either forgot to do this side or they didn't mushroom the shaft enough to hold the lifter in place.
Let us know what you decide.