Your DNS server is returning the addresses for Amazon.
What is the IP address of your DNS server?
Is it possible that you are using Amazon's registered addresses on your network behind a NAT and that the DNS is outside the NAT and therefore knows that these are really not your addresses?
Given that you have a DNS server IP address, I think it is safe to assume that the problem is on the device with that address. And since the DNS server is on the router/firewall, I suspect that the problem is that the DNS cache on that device has been poisoned. Try restarting it.
The reason that the other computers don't have a problem is because each computer keeps its own local cache of DNS results for some period of time. So they will not show the problem immediately unless you reboot one of them. The computer with the problem was probably rebooted more recently than the others.