I've done that too but did it again, and ran the cleaning routine several more times. Still no black ink or not for very long after starting just fine. After the cleaning, you can pull ink cleanly from the head by touching it to a paper towel. I've cleaned (and refilled) cartridges with the integrated print heads many times over the years but have never messed with that on this printer where the cartridge and print heads are separated. I don't believe the head is gunked, it appears clean and I use this printer every day.
Is there truth to there getting air in the printhead which could be extracted while pulling in fresh ink? I've some guy marketing such a double funnel to do this procedure. There's the claim that the head should weigh 60g if properly filled.