As we know, the recovery from VRS requires airspeed. But in VRS, the rotor disc may not respond to cyclic inputs as you would expect, and in fully developed VRS, you may have little or no control over the rotor at all.
Lowering the collective and entering autorotation will give you cyclic control back, and therefore the ability to lower the nose and recover airspeed.
If you don't need to lower collective to regain airspeed, then don't, but if you go to lower the nose and nothing happens, then you must lower the collective to regain some cyclic control.