So what's happening is that the chargetotal variable is correct......that is the amount we want to charge. But when you add up the subtotal, tax, and shipping, it doesn't factor in the MISSING AMOUNT deducted because of the ot_coupon.

We need to have the api modified so that the chargetotal amount doesn't have to equal subtotal+shipping + tax. Either that, or the subtotal+shipping+tax needs to factor in the ot_coupon discount before doing the comparison.