exclude Gift Certificates on products on special

There is a option If checked, the gift certificate cannot be used to buy products that are tagged as gift certificate products.
Is this also possible for products on special or discounted by Virtuemart? Like coupons?

My goal is to sell Gift Certificates with a discount via a coupon. So I have a Gift Certificate product in VM wich cost 100, with a coupon they get a 20% discount so they pay 80 and get a Gift Certificate code with a value of 100 emailed.
When they want to use this in the shop it is better they can't use this to buy products wich have already a discounted price....
Can this be done by a hack?
Or any other way or sugestions?

The solution, without any hacks, is to sell the coupon codes you want:
https://awodev.com/forum/awocoupon/suggestion-box/set-gift-certificates-so-they-can-only-be-redeemed-against#comment-2947

In the latest version, gift certificates can now include/exclude specific products/categories/manufacuters...etc. So you can create a "special" category, add all your special products to it, create a gift certificate that excludes that category, and since you are using awocoupon 1, use the link above to load the gift certificate product with the valid codes.