The exchange rate of vouchers has never been very good and this one doesn't look that bad to me (relatively ). But what I find unbelievable is the remark about the number of vouchers used "After some investigation, the team has extended very special allowances for you to redeem another Le Club members vouchers in such volume, as such we believe we have gone above and beyond to accommodate this request."
Redeeming 8 vouchers is certainly nothing extraordinary and is not against program T&C as said by other posters before me.