It was the Halo championship pack. I figured if I already had everything I would at least get something else worth my while. But, unfortunately, I did not.
Never assume anything. Promotional packs like the HCS pack all have the same asterisk clause on them, that states what happens if you already have all the specialty items in the pack: you get "additional single use REQs". It doesn't state what kinds of single-use REQs, but they always tend to be RP or XP boosts.
You certainly won't be able to get a refund of RP. In general, if something is advertised and it doesn't explicitly state what you'll be getting, you should have no expectations on what you'll get. Because technically, you got what was said you'll get: additional single-use REQs.