The benefit was a South African Travel trip for two with a 15 month time limit. We will not be able to use the trip within the time limit
Your charitable income tax deduction for the purchase is not tied to whether you take the trip, but on how much you paid. For a charitable deduction, you are required to have paid more than the fair market value of the trip. For example, if the retail price for the trip was $4,000, and you paid $2,000, there's no deduction. If you paid $5,000, you can deduct $1,000.
If you can't make the trip, you can "regift" it by donating it to another qualified organization and deducting the amount you paid for it on your 2017 tax return.