I think the Roche limit doesn't apply to your configuration. The Roche limit assumes that the satellite consists of an incompressible material and is held together by gravity, and itself is rotating so slowly that the effect of centrifugal force can be ignored.
Your configuration is different. The "satellite" consists of two unconnected bodies, not only orbiting Earth, but also one another, and this local orbiting means that centrifugal force is enough to compensate the inner gravity force between the two satellites, so surely the centrifugal force can't be ignored in this situation.
Something like the Roche limit would apply to a different (fragile) configuration, if your tungsten ball and your penny were held at distance by a rigid rod between them (and held together by their mutual gravity). Then the Roche limit (or something similar) would denote the Earth distance where this configuration desintegrates because the differences in Earth gravity exceed the inner gravity forces.
The situation you are asking about, is in fact an instance of the Three Body Problem, and there is no simple solution. So, any external gravitational force will to some degree disturb the orbit of the penny and the tungsten ball, no matter whether this happens inside or outside of the third body's Roche limit.