We want few users to access the Dev Hub in a Production environment (and perform development activities like scripting and reload). So trying to understand on 'Access to a user would be provisioned' to access the Dev Hub.
To answer your question, it is not the Configuration system but most probably the Second.
But the reason to create this one is to divide the traffic hitting your main HUB. This will be good if you have many users using HUB and also if there are multiple Developers who has a dedicated proxy. Qlik has already provided you steps in above image...
If you have someone who can do it? You'd need to create a new web address for your Dev HUB and I guess maybe ask your infrastructure team or DBA who has setup this QMC environment for you?