Yeah it's a big no, it says it right in the terms of GCU. Some people have succeeded in the past getting both but that was just dumb luck with a employee who either didn't know or didn't care. There are two minor exceptions to the rule though. One is matching a price listed on BestBuy.com in store & if Best Buy's price is lowered during the return/exchange period.
In a nutshell,
If it's another retailer - No
If it's Bestbuy themselves - Yes