MOND has very little to say about gravity. It claims that f=ma breaks down at sufficiently low values. That, in turn, implies that the rules should still be consistent with these modifications, and that galaxies with apparently different proportions of dark matter (as it's understood) shouldn't exist - all galaxies with similar visible sizes and structures should be essentially identical in gravitational behaviour, and that simply hasn't been demonstrated to be the case.
This galaxy is very much not in the normal range of "sizes and structures", and is highly dissimilar to almost all other galaxies observed.
the stuff about changing F=ma vs changing Fg is kind of pedantic and immaterial to the topic of simulation, given that the accleration due to gravity is the only thing that is being simulated.
I’ve linked above to a paper that attempts to establish what to rotational speed of the clusters should be based on MOND and it’s close enough to the observations that in isolation it still the case that the galaxy either has 1/400th of the dark matter density a normal galaxy would have vs we don’t need dark matter due to MOND.
