Dump and load won't fix logical errors like this. Your fiscal sets and posted transactions are out of synch, probably the worst thing that can happen to a G/L. In other words, GLPOST and GLAFS don't agree, and it takes detailed data forensics to figure out which one is right, so that the other one can be corrected. I've fixed this problem many times in my career, sometimes it was easy, sometimes it wasn't.
I suspect this error happened months ago, so your backups aren't any help. Do you remember a server crash last July?