SWIS v3 Rest API calls not working as domain user

I have this powershell script:

      $server = "server"

      $credential = Get-Credential

      $query = "https://"+$server+":17778/SolarWinds/InformationService/v3/Json/Query?query=SELECT nodeid FROM orion.nodes"

      $results = Invoke-RestMethod -method Get -Uri $query -Credential $credential -DisableKeepAlive

If I use an orion account with NCM privileges it works fine.  If I use a domain account, I get a 403 forbidden.  I've tested in both production and development and it's occurring.  I've changed the account the service runs under to a domain service account, but I still get the same error.

Any thoughts?