Ultimatum Scarabs dropped even though Servent of Order Atlas Node was on

Dear support Team

Report ID: 2086067059

I was Running a Corrupted T16 Map (Crystal ore) and even though I had the Atlas passive Node: Servent of Order activated, an Ultimatum scarab dropped from the boss.

The node Servent of Order specifies: Scarabs found in your maps cannot be Ultimatum Scarabs.

Am I understanding this node the wrong way ?

Thanks.