That link is pretty good at explaining the DNS delegation, TLS and NoScript. However, as DDG runs on AWS, they don't have sole control of their servers anyway.

Edit: output of a DNS/Ping tool I wrote for a book:

    Enter a hostname or IP address:
    duckduckgo.com
    
    Performing DNS lookup of duckduckgo.com
    Complete, duckduckgo.com = 54.229.105.92
    Performing reverse DNS lookup of 54.229.105.92
    Complete, 54.229.105.92 = ec2-54-229-105-92.eu-west-1.compute.amazonaws.com
    
    Complete, duckduckgo.com = 54.229.105.203
    Performing reverse DNS lookup of 54.229.105.203
    Complete, 54.229.105.203 = ec2-54-229-105-203.eu-west-1.compute.amazonaws.com
    
    Complete, duckduckgo.com = 46.51.197.89
    Performing reverse DNS lookup of 46.51.197.89
    Complete, 46.51.197.89 = ec2-46-51-197-89.eu-west-1.compute.amazonaws.com
    
    Complete, duckduckgo.com = 176.34.135.167
    Performing reverse DNS lookup of 176.34.135.167
    Complete, 176.34.135.167 = ec2-176-34-135-167.eu-west-1.compute.amazonaws.com
    
    Complete, duckduckgo.com = 176.34.155.20
    Performing reverse DNS lookup of 176.34.155.20
    Complete, 176.34.155.20 = ec2-176-34-155-20.eu-west-1.compute.amazonaws.com
    
    Complete, duckduckgo.com = 176.34.131.233
    Performing reverse DNS lookup of 176.34.131.233
    Complete, 176.34.131.233 = ec2-176-34-131-233.eu-west-1.compute.amazonaws.com
    
    Pinging duckduckgo.com 4 times
    Ping attempt #1 of 4
    Success
    30 ms
    Ping attempt #2 of 4
    Success
    30 ms
    Ping attempt #3 of 4
    Success
    30 ms
    Ping attempt #4 of 4
    Success
    29 ms
    
    Press any key to exit...

Source code (C#): https://github.com/PacktPublishing/ASP.NET-Core-1.0-High-Per...