Thanks for the thoughts and information.
It appears that the consensus is that there is insufficient time for a vortex ring state to develop, and if it should develop, there would be even less time (and perhaps insufficient stored power) to lift the craft up and out of the VRS.
Re side-by-side rotors;
This subject may also be of little or no relevance to the V-22 Osprey because of its apparent inability to transition the VRS and its very fast autorotative descent rate. However, Sikorsky is proposing their 'Variable Diameter Rotor' with it's lower disk loading. This may result in; the VRS, recirculation, and perhaps landings, becoming a subject of increasing interest.
Thanks again.
Dave