Effectively $7.61 for a general entry and $19.12 for a Gold Class ticket after cashback.
Make sure you go through Cashrewards for each purchase, log into your Groupon account (do not use the guest checkout option), and buy one voucher at a time with the promo code applied.
eVouchers are valid to 31 March 2020
Not valid for use on sessions from 5pm on Saturdays