  Cosmic-ray and gamma-ray observations have yielded several notable excesses
that often lend themselves to explanation by various dark matter
annihilation/decay models. In particular, the AMS-02 anti-proton and positron
excesses have continued to grow more robust with the collection of more data.
This is supplemented by gamma-ray excesses in the Galactic Centre and a
high-energy break in spectrum of electron/positron cosmic rays seen by DAMPE.
In this work we carefully model the magnetic field environments of M31 and M33
and use this to estimate expected synchrotron emissions from electrons produced
via dark matter annihilation. By comparing this to available radio data we
review simplifying assumptions used previously for dark matter hunting in these
environments and produce novel constraints that are capable of fully ruling out
dark matter models proposed to accommodate all the aforementioned excesses
barring that of DAMPE. However, we do show that significant constraints can be
placed upon the DAMPE parameter space with M31 data. In addition to this we
project SKA non-observation constraints for the Reticulum II and Triangulum II
dwarf galaxies and find these have potential to rule out cosmic-ray and
gamma-ray excess-producing models of dark matter, even when the most
conservative assumptions are employed.
