Don't worry man Shar will make them drink from a fountain of blood and then they will have super enraged chaos damage troops and actually begin to be a problem.
Don't you dare underestimate a demon blood infused orc.
Shar previously said that orcs are resistant or even invulnerable to demonic influence, so chances of them doing that are very few.
By the way Shar, what are the Moghtar? I forgot to ask that in the Question Time.