I have a different take. I think that star orbits(planet orbits,moon orbits) are helical, not elliptical. And the edge view allows you to see this. And this also is why our star velocities are so off the mark.....that we need to invent another fiction for our solutions. For no matter how obvious it is.....our equations simply can not be wrong. No matter what we see. Decade after decade.
"...knocked our galaxy's ... dark matter out of alignment..."
'knocked' makes it sound like a single 'faucet washer' object. Silly imo.
If they start talking about fine particulate matter and the inertia & gravity characteristics, essentially fluid flows how would this stuff hold any fixed form at all? Trying to address that would either arrive at something or expose DM as bogus.
'Dark gravity' is Neil DeGrass Tyson's appropriate term.
Thus far there's only evidence for gravity.
Again DM in a galaxy is intra-galacticly immune to gravity and exo-galacticly attracted by gravity.
I guess old academic cliques can't
learn new tricks.