It's a whole paragraph of text, so I'm not surprised Phil wasn't able to take the time to read it. It says she was injured and put into a wheelchair, then when her dad died, that motivated her to train and get better. She was never paralyzed and willed herself not to be paralyzed. Heck, you could even take it as she was already in rehab but it was her dad dying that finally caused her to complete it. It's not exactly an uncommon trope, how many shows/movies/whatever involve a doctor saying "you may never walk again" only for said character to be walking by the end. In the comics, yeah, she was paralyzed (and even that didn't stick) but given the game is set in a world where Batman and apparently commissioner Gordon are dead, it's pretty clearly an alternate continuity.
My Uncle who works at WB games actually told me there's a midgame plot twist. It isn't her training that cures her. Commissioner Gorden actually sends her to Seattle after the attack, and the air makes it so she can walk again. One of her custom gadgets is a special headset, because living in Seattle also made her prone to ear infections.