This problem appears to be an application bug, similar to what was observed in Civilization5 and KOTOR2, with the added twist that no work around is feasible in our driver.
The application apparently calls glDeleteTextures() from a thread where no GLX context was ever made current; although that thread does call glXMakeCurrent(), it does so with a context that is current to another thread (which is illegal) and ignores the ensuing BadAccess X11 error before proceeding to making the glDeleteTextures() call.
The application needs to be fixed.