Sue became a superhero when she graduated, which would most likely lead to a lot of publicity. Not only because she's a new hero, but also because she's the first graduate of the Academy since they reopened. So not only is she getting a lot of attention, I'm sure the press would pry into her past, possibly interviewing other students of the Academy. I'm sure they would have found out that she had dated a Luthor, which would be scandalous because he'd be seen as the son of a villain.

But yes, I kind of agree with you Dizzy. Although possible, it's a bit of stretch.