I want to move my RUT Server to AWS and then I want to create a modified silent .exe file or silent .msi install and bulk update ALL of my host computers for ALL of my clients. I want to have a primary RUT Server on AWS and then have a secondary failover RUT server somewhere else.
Yes, this is possible in case if you configure a custom MSI installation package with updated settings that point at your new server's address and then will propagate it across your remote machines using Remote Install Tool as described in this guide - this way the remote Hosts settings will be updated.
As for the failover server - unfortunately, there's no failover mechanism to automatically switch between RU Servers yet. However, in this case, you can use the DNS trick. Please note that you should use a DNS name for your server that points at your main Server's IP address. If your main server at AWS is down, then you can simply update your DNS record and point it at the backup server's IP address (the server should be running of course). These days DNS propagation literally takes seconds or minutes at the worst, so your remote connections will be quickly up and running again.