ok - maybe 28 (4d10+6) psychic for phantom boulder?
rock - 28 (4d10 + 6) bludgeoning damage + 11 (2d10) necrotic damage?
(so both are a little weaker than melee attack?)
Rock bowling could also be 28 (4d10 + 6) bludgeoning damage + 11 (2d10) necrotic damage, but only once a round as total...