So...obviously they are reselling them somewhere else that has a similar assurance of re-payment. The question is, who is that? I'm guessing that their buyer gives them a shopping list of items they need and only then do they offer to purchase them through "gazelle".

There are a lot of super, super shady "electronics dealers" who sell crap using high pressure techniques, and who keep costs low by not having inventory. I'm guessing that these people are gazelle's buyers.