You could plant that at an angle so the surviving branch is vertical. If planted as is, the branch will arch up to vertical on its own. If planting at an angle results in some roots protruding above the soil, just trim those roots off and cover the spot with soil or mulch.

Probably best to plant at an angle with branch vertical, as the junction between the stump and branch may not be strong enough to support such sideways growth. The branch can be straightened somewhat by taping a stiff stick, bamboo piece, or rod at 3 or so points along the branch.