When last week did you place the order? For me it sometimes goes pending the next day, other times it takes 3-5 days. Since your purchase was a physical item that is sure to be eligible (unlike GCs that they say are not) you can always email them about it after a few days.
I try to just order through RMN when I am getting a discount anyway. Like the Amex credit they had for Staples and for BB, or what I did a few posts back (bought discounted DGCs at Sam's using discounted cards). That way if RMN does not credit (since buying GC is technically not eligible and YMMV) I still got them at a discount and can't really get too upset (although I still would
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