He definitely wasn't. Williamson included her in the first issue of Dark Crisis, so he must've been unaware of how her book ended... and that she therefore wouldn't even have been there when the rest of the League disappeared. If he didn't know, then either editorial didn't know either (which doesn't make sense), or they didn't have plans to dispose of her.
Also, don't forget she had a TV show. Did they already know it had been axed when the comic's finale was written?