The Large Hadron Collider reveals how far antimatter can travel through the Milky Way

"The first suggested source for antinuclei is the interaction between high-energy cosmic radiation, which originates from outside the solar system, with atoms in the so-called interstellar medium that fills space between stars. The other suggested source of antinuclei is the annihilation of dark matter particles that are spread throughout the galaxy. While scientists know little about dark matter, they are certain that it is not comprised of particles like protons and neutrons that make up the everyday matter that forms stars, planets and us. Scientists believe dark matter, in contrast, is comprised of a wide range of particles with colorful names like WIMPs (weakly interacting massive particles) and MACHOs (massive compact halo objects). One scenario suggests that when dark matter particles collide, they annihilate into particles that then decay into light matter and antimatter particles, like electrons and their antimatter counterpart, positrons. If dark matter annihilation is indeed a source of antimatter in the universe, antimatter could point the way to dark matter, scientists hope."

So, is DM confirmed in this report as to DM being a WIMP or MACHO? The paper, Measurement of anti-3He nuclei absorption in matter and impact on their propagation in the Galaxy | Nature Physics

States, "Propagation modellingThe possible sources of antinuclei in our Galaxy are either cosmic-ray interactions with nuclei in the interstellar gas or more exotic sources such as DM annihilations or decays. Cosmic rays mainly consist of protons and originate from supernovae remnants, whereas DM has so far escaped direct or indirect detection but its density profile can be modelled88."...Although coalescence-based models can successfully describe antinuclei production, the model uncertainties are still relatively large, which leads to substantial changes in the magnitude of antinuclei fluxes22,30,61."

Apparently, DM is not nailed down yet as to exactly what it is.