As we have no actual evidence that the user was botting during the service, we cannot go based off assumptions.
For the refund calculations I will be using the gp/xp for the entire intended service and not your higher 1-30 rate - my calculations put you at doing 286,824 gp worth of the service - meaning the appropriate refund would be 6,747,696 gp. @Luna please work with the user to refund this amount over Skype and both of you post here when it is complete.
@HauntingEchoes it seems clear from the Skype screenshot that Luna informed you they would not be able to start until the next day, so this is not a valid point in the dispute.