Hello,
We don’t control how the codes are redeemed; that sits 100% with Discord as our partners on this. I know you’ve read the article, but as it states in said article Tracker.gg x Discord Nitro Promo – Discord, there are certain restrictions and FAQ’s for the issue.
Discord passes us the codes, we pass them to users, and we’re limited on what we can do once the code is in their hands.
Apologies