I'm not familiar with the error, but if your backup loads fine then maybe you're okay?
Go to edit>preferences and in the general tab look for "default catalog" and see if you can change it to "Load most recent catalog". Then it should open the backup catalog if it was the last thing open in lightroom. You can also move the corrupt catalog to a different location so you have it if you need for some odd reason, but if you don't move it, lightroom will always know it's there. Or you can just delete it, again if the backup catalog doesn't show the same corruption.