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We present centimeter-band and millimeter-band afterglow observations of five long-duration γ-ray bursts (GRBs; GRB 130131A, 130420B, 130609A, 131229A, 140713A) with dust-obscured optical afterglow emission, known as" dark" GRBs. We detect the radio afterglow of two of the dark GRBs (GRB 130131A and 140713A), along with a tentative detection of a third (GRB 131229A) with the Karl G. Jansky Very Large Array (VLA). Supplemented by three additional VLA-detected dark GRBs from the literature, we present uniform modeling of their broadband afterglows. We derive high line-of-sight dust extinctions of A V, GRB≈ 2.2–≳ 10.6 mag. Additionally, we model the host galaxies of the six bursts in our sample, and derive host galaxy dust extinctions of A V, Host≈ 0.3–4.7 mag. Across all tested γ-ray (fluence and duration) and afterglow properties (energy scales, geometries, and circumburst densities), we find …