  Energy spectroscopy of strongly interacting phases requires probes which
minimize screening while retaining spectral resolution and local sensitivity.
Here we demonstrate that such probes can be realized using atomic sized quantum
dots bound to defects in hexagonal Boron Nitride tunnel barriers, placed at
nanometric distance from graphene. With dot energies capacitively tuned by a
planar graphite electrode, dot-assisted tunneling becomes highly sensitive to
the graphene excitation spectrum. The spectra track the onset of degeneracy
lifting with magnetic field at the ground state, and at unoccupied exited
states, revealing symmetry-broken gaps which develop steeply with magnetic
field - corresponding to Land\'e $g$ factors as high as 160. Measured up to $B
= 33$ T, spectra exhibit a primary energy split between spin-polarized excited
states, and a secondary spin-dependent valley-split. Our results show that
defect dots probe the spectra while minimizing local screening, and are thus
exceptionally sensitive to interacting states.
