I think the website that features the petitioning for a VC for Simpson is
www.anzacs.org
There was an Australian politician who was campaiging for a VC to be awarded to Simpson and also two others from WW2(whose names I cannot recall) but I don't think many of her colleagues have been taking her seriously.
While many brave acts have gone unrewarded by the VC, I don't think there can be a retrospective look at acts of bravery.
Say for example if Albert Jacka was now awarded a VC for his actions at Pozieres overriding his MC, what's to stop every other relative of a Tom, Dick or Harry who won a medal other than a VC from petitioning to have the award upgraded.
Hate to think that would come about.