From the preprint link at the top's page 6, after Eqn (23): "While this study demonstrates that galactic rotation curves can undergo modification due to stochastic fluctuations, a phenomenon attributed to dark matter, it is important to acknowledge the existence of separate, independent evidence supporting ΛCDM. In particular, in the CMB power spectrum, in gravitational lensing, in the necessity of dark matter for structure formation, and in a varied collection of other methods used to estimate the mass in galaxies.
These now form an important set of tools with which to test [our] theory".
Other lines of evidence like the one at your link just increase the ability to test their theory (which is meant to solve some quantum gravity problems at very small length scales) at very large length scales.
They are not motivated by the desire to prove MOND is correct or that cold dark matter doesn't exist. Rather they can show that in certain restricted circumstances their theory allows for nearly-MOND-like orbits. So their theory survives a small but important hurdle imposed by our observations of nature (we observe MOND-like orbits).
Elsewhere in the comments someone asked the good question of (highly paraphrasing) whether this success is wiped out if a distribution of dark matter is added to their SdS-like universe as the generator of some of the observations normally taken as proof of \Lambda-CDM. That question is closely related to the final sentence in the quote above, and answers are hard to guess at.
Other lines of evidence like the one at your link just increase the ability to test their theory (which is meant to solve some quantum gravity problems at very small length scales) at very large length scales.
They are not motivated by the desire to prove MOND is correct or that cold dark matter doesn't exist. Rather they can show that in certain restricted circumstances their theory allows for nearly-MOND-like orbits. So their theory survives a small but important hurdle imposed by our observations of nature (we observe MOND-like orbits).
Elsewhere in the comments someone asked the good question of (highly paraphrasing) whether this success is wiped out if a distribution of dark matter is added to their SdS-like universe as the generator of some of the observations normally taken as proof of \Lambda-CDM. That question is closely related to the final sentence in the quote above, and answers are hard to guess at.