is there any way to test the authentication in WAS without actually run a discovery or vulnerability scan?
Not at this time, but it is a much-requested feature and it's actually under development right now. For now your best bet is to run a discovery scan and use an option profile with a small number of max links in scope, such as 50.
What I have done is create a custom list with the authentication QIDs and then run a customized scan (not sure if this would solve your problem however)
Are you able to share the QID list you're using?
"it's actually under development right now" ? You mean it is under development since 2012.
WAS Authentication 'Test' button?
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