On the one hand AWS offers a wide range of different support levels. You will get answers to all your questions regarding AWS infrastructure. This AMI is using the services EC2 and EBS. Also AWS offers a great documentation including “Windows Server on AWS”. See Link below.
DNN Platform (DotNetNuke CE) Support
On the other hand DNN Corp. offers enterprise level support for their commercial products (“evoq”). Take a look what DNN Corp. is offering and consider to use their commercial products if they fit better to your approach or use case.