Speedgrader only shows how much time the student took to complete the quiz and not how much time the student had to take the quiz. The only way to see how much time a student has is by looking in quiz moderation and that doesn't mean that the student had that much time for that exact attempt as you can edit quiz moderation after the quiz was completed. As well the API has this same issue as when you give extended time after an attempt is made it will only show the new extended time even though the student didn't have that extended time when they did that attempt.
In Speedgrader just have it display "This attempt took 15 minutes out of the allowed 25 minutes" instead of "This attempt took 15 minutes"
