My main concern would be that a ring set was sent out with a center stone set noticeably crooked. If that is truly the case, quality conrol was asleep at the wheel, not to mention the jeweler who set the stone. I wouldn't be happy either and I wouldn't expect to have to pay to ship it back.
However, the problem is that we're only getting one side of the story, and I don't blame the vendor one bit for not getting into a flaming war on a message board.
There have been others lately who copied and pasted emails on the board and I think that's manipulative. I wonder how these people would feel if emails they had sent were suddenly public.
I feel bad the OP may have gotten a defective ring. I have had great experiences with Moissaniteco personally.
I think that as a company, everything you say, everything you email, you need to be aware that this will be passed on (whether to friends, or publicly).
I would love another side of the story, which is why I would love for a Moissaniteco owner to respond. Quite frankly, the staff I have spoken to have been unhelpful when I bring my questions about...you know what? Stuff happens. Maybe it was a newbie who made the ring? Maybe it was a genuine mistake. You know what, that happens. But it was 100% their fault, and I am frustrated I have to be responsible for their screw up