In Baahubali: The Beginning, Persian warrior Aslam Khan was shown but why didn't he have a role in Baahubali 2: The Conclusion? What is the significance of his scene with Kattappa when he was never used again in the second film?
He might have a role in the second as well,
But the possible reason was the lack of screen time which is why he has no role in second movie.
The movie has runtime of 168 minutes (171 for Tamil), of which around 130 minutes was taken by story of Amrendra Baahubali.
Since the fight sequence between Mahendra Baahubali and Bhallaldeva was important part to show, the role of Aslam Khan wasn't considered at all.
Lack of screen time was also the reason why Tammannah's role of Avanthika had less screen time.
Another possible reason can be the protest by Vatal Nagaraj and his party against Sudeep (Sathyaraj was also part of this, but he apologized later) regarding the Cauvery water issue in Karnataka.
What is the significance of his scene with Kattappa when he was never used again in the films?
His role in first movie had a purpose which was to let audience know about Kattappa's warrior skills and slavery.
There is no official statement I could found regarding this, though.