Schematic Extreme Case Velocity Dispersions: CIRCULAR Orbits
For circular orbits there is no dispute. Any model of gravity that predicts constant speed trajectories at constant distance from the mass center would yield similar curves if all orbits are circles of random size and orientation.
Schematic Extreme Case Velocity Dispersions: RADIAL Orbits
If all orbits were randomly oriented radial trajectories, Newton predicts maximum velocities at the center, whereas the Space Generation Model predicts that velocities go to zero at the center. Observationally, this would be revealed as a steep drop in the proper motion velocity dispersions near the center.
These extremes are far from what would be found in real world star clusters. But by considering them, we can see why the Space Generation Model predicts that clusters would tend to have more circular orbits than radial orbits. A preponderance of radial orbits would cause the cluster to collapse.