Green’s Dictionary of Slang

(Aus.) phr. denoting absolute finality.

1989		M. Walker How to Kiss a Crocodile 22: All a hungry croc had to do was slowly open wide and they’d end up straight in its mouth. Snap - all over red rover!
1999		Hansard (Aus.) vol. 227 6937: There are going to be three shipyards completing — all over, red rover in terms of what they are manufacturing.
2011		P. Fleming Falling into History 163: If he were ever to read this manuscript [...] it’d be all over, Red Rover—no more memoirs, in fact, no more Kim, Eight, and me.