Also, aside from knowing how to prevent this from happening again, does it matter if the wing was on fire before or after it came off the plane?
Aside from knowing how to prevent this from happening again, no, except perhaps to help identify and understand the sequence of events that occured. If a fire precipitated the failure, the steps taken to prevent future occurances might be quite different than if the failure occured for other reasons like corrosion, fatigue or something else. That was the only reason I had for thinking it may be important to know. Time will tell.
Best regards,
Westhawk