Superficvially, but it has characteristics of the red kangaroo too (white tail tip, white blaze on cheeks). I would not be surprised if this was an Grey x Red hybrid. Or maybe a Wallaroo x Grey Hybrid.
I also couldn't find any reports on red - grey hybrids, found however mentioned hybrids between Macropus fuliginosus x M. giganteus which were bred several times during the 1980-ties at Osaka Zoo in Japan .