One thing you can do is perform a trademark search on uspto.gov and take a screenshot showing your game name has not been trademarked by anyone (and if you really value your game name, you can trademark it but that will cost you a few hundred dollars).
I haven't had much trouble with Amazon but often I've got into a situation with Apple App Store submissions where I have to guess what their real objection is (and sometimes conclude the reviewer is just determined to reject the app). I've had one case where Apple said I violated one of their trademarks, but it wasn't a trademark, it was just an animation that resembled one of their TV ads. They have an army of reviewers who just spend a few minutes on each app so there's going to be some sloppy and opinionated reviewing. It's also possible that it got flagged by some automated process, which I've had happen on Google Play, and it's hard to argue with a computer.
If no one else has a claim to the name Botty, then I can only speculate they think any name with Bird is too close to Angry Birds (I've had a lawyer for the hip hop fashion line FUBU contact me to say my Fugu Games infringed on their trademark), and if that's a real sticking issue, then maybe the easiest thing is to just change the name on the Amazon Appstore. In the worst case you might have a reviewer who is determined for some reason to reject your app and just keeps coming up with new problems. When that's happened to me with Apple, I've waited a few months and resubmitted in the hopes I get a different reviewer.