The reasons given for the death of Haman's ten sons is their active role in halting the construction of the beis hamikdash (this is one of many midrashic sources)
My question is why was it necessary to include them in the megillah?
Haman had a son named Shimshai the scribe who was also actively involved in the halting of construction AND played a role in the story of purim. He had tried to erase Mordechai's name from the book of chronicles which kept a record of Mordechai's life saving advice to the king. (Source for writing stop work order Source for Shimshai as Achashverosh's scribe)
If Shimshai - who was involved in the Purim story- is not mentioned in the megillah, why then were his 10 brothers who (seemingly) did not have a role in the Purim story mentioned so prominently in the megillah?
(This is NOT a duplicate of this question)