Scanning Non AD-Computers

I can scan my Non-Domain joined machines in my DMZ if I create credentials in PDQ that match the local accounts on the DMZ boxes.  The problem is that I have to make those credentials the default scan credentials in PDQ.

Is there a way to make the "Scan User" default to the created local account credential just for a Scanner or Collection?  This would keep me from having to change the default back & forth before every scan.

I created a new scanner for "Local Administrator Accounts" for the DMZ servers but my only choice for "Scan User" is "Scan User, Local System and Logged On User" ... I can't select my "Local Administrator" credentials I created.