  Type Ia Supernovae (SNe Ia) are a critical tool in measuring the accelerating
expansion of the universe. Recent efforts to improve these standard candles
have focused on incorporating the effects of dust on distance measurements with
SNe Ia. In this paper, we use the state-of-the-art Dark Energy Survey 5 year
sample to evaluate two different families of dust models: empirical extinction
models derived from SNe Ia data, and physical attenuation models from the
spectra of galaxies. Among the SNe Ia-derived models, we find that a logistic
function of the total-to-selective extinction RV best recreates the
correlations between supernova distance measurements and host galaxy
properties, though an additional 0.02 magnitudes of grey scatter are needed to
fully explain the scatter in SNIa brightness in all cases. These
empirically-derived extinction distributions are highly incompatible with the
physical attenuation models from galactic spectral measurements. From these
results, we conclude that SNe Ia must either preferentially select extreme ends
of galactic dust distributions, or that the characterisation of dust along the
SNe Ia line-of-sight is incompatible with that of galactic dust distributions.
