Q:

Where can I see a list of scratch-orgs created by all the developers?

Our production org has the Dev-Hub featured enabled. I know there are more than a couple of scratch orgs created. I want to see the entire list and the natural place to look for them seemed to be the Dev Hub. I am not able to see them over there.

Edited to Add:
So far after talking with salesforce support, I have learned of a command that I can fire from the Powershell Terminal within Visual Studio. 
sfdx force:org:list --all
This works partially, in the sense it gives me a list of my orgs but not all the active scratch orgs in the organization. 

A:

This is in the documentation:

Log in to Dev Hub org as the System Administrator or as a user with the Salesforce DX permissions.
From the App Launcher, select Active Scratch Orgs. A list of all active scratch orgs is displayed.
To view more details about a scratch org, click the link in the Number column.
To view the request that was used to create the scratch org, click the link in the Scratch Org Info column.

Note that you can't see the list of orgs if you don't have permission; make sure you're logged in as an administrator or have the relevant permissions.

