Gift receipts also expire at 90/120. They have the purchase date printed on them, and the one I have in front of me says "some items have a return policy that is less than 90 days." If the regular receipt won't work, neither will the gift receipt. Your only option then is ID return if the system will allow it.
Not everything is raincheck eligible. And some items that say "no raincheck" in the ad can still generate one (found that out over Black Friday) 🙄. So in HLN13's case, I would amend the wording to "you can ask at GS if it's possible to receive a raincheck" rather than "GS will give you one".