$480000 sounds like a fairly reasonable payout in this case, and it sounds like you aren't entirely opposed to that (or at least the amount of her huge medical bills, whatever it is), so I don't think we necessarily disagree (except others have covered serving vs. brewing temperatures). I have a bone to pick with this argument:
Those 700 incidents were over a period of something like 13 years when McDonalds sold billions of cups of coffee. I number crunched the statistics once. If you lived 5 miles from McDonalds and drove there to buy a cup of coffee and took it home, you were more likely to die in a traffic accident than to scald yourself by spilling their coffee. If their coffee was too dangerous for the public, then so is every car on the road.
That's a pretty nonsensical argument. If I had to swim through shark-infested waters to an island to go rock climbing, then the risk of me dying from a shark attack would exceed the risk of me dying from a rock climbing accident.
Yes, cars are dangerous, and that's why their use is carefully licensed and car manufacture, sale, and driving is one of the most regulated industries. It's an irrelevant benchmark because driving cars is not drinking coffee, and even if it were relevant it makes for a very poor benchmark in your case a lot of things can be safer than cars and regulated less than cars and still regulated a lot more than coffee.
In this case, the problem wasn't even that McDonald's served the coffee this hot, it's that it served it this hot with no warning.