Then something strange happened. He grasped the gun like removing a Glock slide and it moved! Oh well...
Went back in, loaded it up and shot some more when it froze again! I tried the Glock-grip and some smacking it on top and sides with my hand. Unstuck! What?!

Glock-gripped it - not this time podnuh! Got a flashlight and screwdriver and the slide lock-back lever was seemingly jammed against the breech face. Pried it down, slide free. Took it home and cleaned like a fiend!
I took a fine, small miniature flat file and dressed down the rear edge of the lock-back lever and a tiny peened/rolled edge. I smoothed it all and cleaned, lubed and re-assembled. Anyone ever had this happen? I searched and found a number of "slide locked back" threads but none like this. Ideas? Thanks!