The matter has been resolved after the discussion on this forum; It took ~2 months to fully resolve the issue, and now the original S&H has been refunded. I want to thank everyone on the forum for their input!
If you're new to this post and don't feel like reading all of the posts, here's the gist:
I ordered two Origami bikes and returned them due to quality issues, which I believe merits a full return, including shipping and handling both ways. At first, only the cost of the bikes and the return S&H were refunded, but after some communications with the the owner, I have been given a refund of the original S&H.