Cannot Obtain Chimeral Inscribed Ultimatum

I was in a party in Act 3 for the Chimera - and my party member got the Chimeral Inscribed Ultimatum while I did not.

I've tried killing the Chimera again, and it won't drop. So I have no way to complete the "Trials of Chaos" quest to obtain the 2 ascendency class points.

Any help on this one?

Thank you...

I have the same issue. I seen another forum with many with the same issue.