Yep, Amazon is good about returns.
I just dealt with them yesterday about a return and will receive a full refund, although some time has passed since the purchase. It concerned the cover/case I bought for my new iPad I got last month at Costco. It took me a while to determine that the front cover (with a magnetic interior that shuts down the iPad when the cover is closed) has too powerful of magnets in it, and that folding the cover around the back (like a book cover) also would shut down the iPad from the backside! It never happened with our previous iPads, nor was it happening with my wife's new cover for her new iPad. Hers is a different brand, so once I figured out it was the cover and not the iPad acting up I bought myself a cover; same brand as wife has last week from Amazon. I put it on my iPad yesterday, and all is well with new cover and my iPad now. Apparently, the first cover I bought was poorly engineered and made with stronger magnets than necessary. It's kind of a weird problem I thought I would share.
Anyway, good luck with your replacement Fire tablet.