You can't use Hamilton's Tokenotes with a Mars validator because Hamilton's are magnetic, Mars are optical.
The Mars coupons are very limited because the interface doesn't allow for the coded pulses that are sent from a Hamilton validator used with Tokenotes. You could, in theory, use a programmable relay to "catch" the bill pulses from the Mars and send them to the Goldline, and if you had a coupon worth an amount different from a bill denomination that would be sent as a Tokenote credit.
There is a Mars coupon but the Goldline will only read it as cash. I think I can fool the Goldline into taking a coupon for a non-bill amount (like $4) and reading it as a Tokenote code. Do you know how Tokenotes work?