Is there a way to query for items in the Skills Backlog? This is the tab in Omni-supervisor that shows any work that haven't been accepted.
From OmniChannel SOAP Api guide , the Object to query is PendingServiceRouting .
And you mentioned its for Skill based and not QueueBased so that would be your filter.
SELECT CapacityPercentage, Your_Fields FROM PendingServiceRouting WHERE RoutingType = 'SkillsBased'