It’s the movement holding screw that holds the movement down to the case. Needs putting back on. If you look just below the Officine Panerai writing in between the plates you will see the screw hole, with a groove in the case for the metal tab to go into and then screw it down.
You can not ignore this. If the movement is not attached on both sides, the movement will move loose within the case. You (or better your watchsmith) need to drill out the hole and get the stucked piece out of the hole. Then you can use a new screw and attach the movement also on this side again to the case.
Thanks for the info! To try to find a strategy (since I live in a rep-unfriendly place regarding watch smiths) what could happen if I keep using it? Will it destroy the movement or will it work “not so well”? In the rotation I use this Pam once every 3-4 weeks... the “charge problem” is not that relevant.
Before anyone drill or press anything, try a screwdriver with a small drop of epoxy glue on its edge.
Anything to avoid machining inside the case
opticians are far more used to this exactly bolt situation and most likely they will have develop tools and techniques about
Worst case scenario buy a new Asian 6497-2 high beat and swap the engraved bridge in. Voilà new movement for cheap