Misleading advertising using Credit Score as excuse

Please explain why a Vodacom contract been approved to a client with a Credit Score of 685, to get a special at Incredible Connection Bloemfontein for an IPhone 11 for R599, with a voucher of R5000 for over 36 months, why must said client pay in R10 000? To get the deal? Where does this R10k goes? Does it improve your Credit Scoring?