.See this: http://cosmology.com/GalacticWalls.html
The splitting black hole big bang is supposed to be the origin of the "great wall structures" even BEFORE plasma is created.
So the speed of the galaxies to concentrate and form great walls should be is not an issue in the calculations of wall creation by contraction.
see also: https://www.academia.edu/6781821/The_Navel_Cord_Multiverse_with_Raspberry_Shape_a_Super_Symmetric_Entangled_12_Fold_Bubble_Universe
For Quantum FFF Theory see: http://vixra.org/author/leo_vuyk
For posters of Q-FFF theory: https://www.flickr.com/photos/93308747@N05/albums/
Below: Left 40% infra red CIBs according to Q-FFFmodel: dual splitting Galaxy Anchor Black Holes, starting to form stars in between. see: also: https://www.sciencedaily.com/releases/2016/03/160310111846.htm