CB’s traditional position has been no refund at all. You have only the right to reschedule. However, my understanding during this Covid period is that CB has been refunding the amounts paid if it cancels a test, but you have the option to reset it for a later date. It is also refunding if a student does not take a test actually given because of feeling sick on the test day – it is telling students to stay home if that is the case.
It appears you may fall a little in-between its Covid refund policies, i.e., you did not take the refund when June and August were cancelled, but instead you rescheduled, and your DD has not missed a test actually given because of sickness.
You may want to call and discuss with someone in authority at CB whether a full refund should be given, explaining that it was CB that cancelled the two tests and now it is useless to take one.