The kangaroo is a wallaby and it has been living in the wild on the island of Lolland for years. The animal association comments that it is totally possible for a kangaroo to survive in the wild in Denmark, eating grass, sprouts, herbs, bark, leaves and so on, and it looks well fed and fit. The only problem would be hard winters where a kangaro could suffer frostbites on ears and tail.
Normally kangaroos geting loose in Denmark, meets with a car sooner or later, resulting in its demise. This one is one smart kangaroo survivng for years now.
If it's happy and doing well, perhaps all it needs is a shelter from the cold and to otherwise be left alone.
SvarSlet