You can turn the screw but it won’t come out right?
If this is the case, the treads on the screw is stripped.
I have seen many many many of these and were always able to get them out.
There are a few options.
On the first sec @ 12 models, I always removed the screws and drilled a hole through the metal lug between the 2 links so that you can look through it. If one screw get stuck, you will be able to push a thin rod (like a needle) through the other side to push it out while you screw it loose.
(hope to make myself clear)
On the later models they came standard with the drilled through lugs.
Back to your problem.
If you can remove one screw, try to find out if the lug is drilled. If so, you can remove it like described above. Just put a thin rod in it and see how far it goes in.
If it isn’t drilled and it was a rep case, I would drill it out like I described above. During the drilling the screw will come out because you push it out with the drill bit. Just be very careful with the drilling. You do not want to damage the treads of the lug.
I would not do this with a gen case of course.
The other option would be to install the strap back on it.
Then push the strap down to create some pressure between the lug and the link.
Because of this pressure, you should be able to screw it out.
To make myself clear, you need to unscrew it while you press the strap down.
The last option which worked for me in the past was to use some super glue on the top of the screwdriver. You just glue the screwdriver on top of the screw and very gentle unscrew and pull at the same time.
This should work
If you get them out, I can get gen lug screws for you if you need them ;-)