Is https://www.openstreetmap.org/way/54455280/ really oneway? On Kartaview (https://kartaview.org/details/6073609/381/track-info) it looks like a right turn from St. Georges Road into Merri Parade is possible.

Routing uses https://www.openstreetmap.org/way/1186701654, then https://www.openstreetmap.org/way/1186701656, which would be an awkward 90 degree right turn. 