Is there any way to influence what level mobs are spawned

I am slowly working my way through the Oratan Payback Mission XVII (Day 10/60)
It is the final leg. I have to kill 100 Oratan Miners, Dominant to Elite. and 50 days to go
Sadly I only have the skills and equipment to have any chance with Dominants, Alphas, and Old Alphas.

There seem to be only two places they spawn at these levels, in Ark underground at The Abyss and Limbo Firebase.

In the spawns Dominants to Old Alphas appear rarely (heaps of the really high levels thou, or levels below what I need)

Is there any way to cause the three I need to spawn? Any advice info would be greatly appreciated