We give a quantification of residual finiteness for compact hyperbolic 3--manifold and 4--manifold groups that virtually embed in specific right-angled Coxeter groups arising as reflection groups for all right polyhedra in ${\bf H}^3$ and ${\bf H}^4$, respectively. We show for this class of groups that their residual finiteness growths are at most linear in terms of geodesic length.
