Green’s Dictionary of Slang

(N.Z.) to escape, to run off.

1938		F. Anthony ‘Winter Feeding the Herd’ in Me And Gus (1977) 82: I hooked off on my own and rambled aimlessly about until the sun was getting low.
1940		F. Sargeson ‘A Man and his Wife’ in A Man And His Wife (1944) 75: If Ted saw her coming he’d hook off.