  The Fermi-LAT observation of a gamma-ray excess from the galactic-centre, as
well as the PAMELA, AMS, and AMS-2 anti-particle excesses, and the recent claim
of a Fermi-LAT excess in the Reticulum-2 dwarf galaxy have been put forward as
signatures compatible with of neutralino dark matter. These are of particular
interest as the neutralino annihilation models which fit these observations
might have observable consequences from radio to gamma-ray emission. Since dark
matter is expected to be a major matter constituent of cosmic structure, these
multi-frequency consequences should also be common to structures across the
mass spectrum. Thus, in this work we make predictions for the multi-frequency
spectra of three well-known sources dominated by dark matter, e.g. the Coma
cluster, the galaxy M81, and the Draco dwarf galaxy using models favoured by
dark matter interpretations of the aforementioned observations. We pay special
attention to the consequences for these models when their cross-sections are
renormalised to reproduce the recent gamma-ray excess observed in the
Reticulum-2 dwarf galaxy, which throw a dark matter interpretation of this
excess into doubt. We find that the multi-frequency data of Coma and Draco
disfavour the dark matter interpretation of the AMS, PAMELA and Fermi
anti-particle excess. Models derived from Fermi-LAT galactic centre
observations present somewhat lesser conflicts. We determine the detection
prospects of the Square Kilometre Array, the Cherenkov Telescope Array, as well
as the ASTROGAM and ASTRO-H satellites for the studied models. This
demonstrates that ASTRO-H is well positioned to probe the X-ray emissions from
neutralino annihilation. Thus, multi-frequency observation with the next
generation experiments will allow for unprecedented sensitivity to the
neutralino parameter space.
