Let's see.... Hmmmmm...... Sounds like a very interesting perspective to me. Yet using the very data you present, let's just stick with the Forbes article for now, there should be 5.4 alien civilizations in our galaxy that are in our range of the electromatic spectrum if 85% of matter is in the Dark Matter spectrum.
That just gave me a great idea. We should coin a new phrase, call it the DM Spectrum. Apply it to all the invisible stuff that dark matter could represent.
So.... back to the original focus of my comment - where are the other 5.4 civilizations that should be emitting signals in our EM Spectrum? Not caught up to us yet?