The difference is, it is completely illegal for you to drive whilst having a hypo, not only is is very dangerous to do so, you can have your license revoked! Now it is at the company's discretion whether they take this in to consideration, and subsequently decide to continue with the fine. But it is in NO way comparable to someone who has injured their ankle. These are the kind of comments that really grind my gears (excuse the pun). In any court, would a judge favour a break in law, or a break in contract? Legality does come into it, because criminal law is superior to civil law, and if it came down to taking it to court, and she could prove that she was in fact having a hypo, the judge would more than likely rule in favour of her.
So chin up to the girl who got the fine, from one diabetic to another, not many 'type 0's' understand our struggles, but there are plenty of people out there who are also battling every day to live a normal life, with a disease that makes normal every day tasks hard.