a!pickerFieldUsers Results are Not Visible to any Non Admin Users

Hello, 

It seems that all user pickers in our app are not working properly. When logged in as any Non Admin user, the only result shown is the logged in user. When I login as an administrator, I can see all users. I am using our All Users group as the groupFilter so I don't know why it isn't working. 

All Users Group Properties
visibility - restricted (only members and admins)

membership - closed (admins must select all members)

privacy policy - low (members can see eachother)

It seems like with our settings, all members should be able to see eachother. 

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