  The compound SmB$_6$ is a Kondo Insulator, where the lowest-energy bulk
electronic excitations are spin excitons. It also has surface states that are
subjected to strong spin-orbit coupling. It has been suggested that SmB$_6$ is
also a topological insulator. Here we show that, despite the absence of
time-reversal symmetry breaking and the presence of strong spin-orbit coupling,
the chiral spin texture of the Weyl cone is not completely protected. In
particular, we show that the spin-exciton mediated scattering produces features
in the surface electronic spectrum at energies separated from the surface Fermi
energy by the spin-exciton energy. Despite the features being far removed from
the surface Fermi energy, they are extremely temperature dependent. The
temperature variation occurs over a characteristic scale determined by the
dispersion of the spin exciton. The structures may be observed by electron
spectroscopy at low temperatures.
