Inferno – “Angel, angel, burning fear” [Campaign 5 – Mission 1]

I still can't complete the mission... I'm starting it for the fourth time, and the last time I got the furthest, killing all the Painseekers and Pain Lords (or something like that). But then a gate opens, and a brown "deathbringer" comes out... I have a large army, but I desperately lack the money to buy them all. In the end, the brown one (and it's just a secondary unit!) defeats me easily.

I want to know: is it possible to earn 250 points for Blood Path development in this mission? I didn't recruit anyone, I attacked everyone, and I only have 145 points. I completed the mission. Will there be problems later because I didn't complete the task?