Unfortunately discounts can only be created for specific items, it's not possible to exempt items from specific discounts.
That does mean that the only way to do this is to create 97 different discounts for the eligible products which each use the same code (the code can be shared, but be sure to give each discount a unique name).
It will be a chore to set up on the backend but the end result will be that your buyer can claim any of those different discounts by entering just one code in the cart so it won't impede the purchasing process.