This sounds like a super fun simulation to run. Do you have recommendations on simulation software?

I found these in a quick search. I have a couple 64 core machines available.

https://wwwmpa.mpa-garching.mpg.de/gadget/

https://rebound.readthedocs.io/en/latest/

http://www.tapir.caltech.edu/~phopkins/Site/GIZMO.html