As an Australian I would struggle significantly unless you were to also transport me geographically.

This may have already been covered but whilst there might not be mammals that appear green to human eyes there are certainly mamals that appear green to the prey/predators in their environment.

Perfect example is a tiger who (to us) stands out like a sore thumb with its orange fur but is perceived as green with black stripes through the eyes of its prey, making it very well camouflaged in the jungle.