The entry for these in the WD army list states that they can be taken as DOW in a DOW or Chaos Dwarf army but it does not state what slot it takes up.
Any thoughts - my feeling is that DOW choices for most armies should be rare unless it states otherwise. However, for DOW armies themselves, a lot of choices that are rare for other armies are special for them.
Grumpmas confused - head hurt.
(I only ask because I’m assembling a Gnoblar horde so I will have a unit of them to play with)