The optimal choice if you're just told you're gonna play this game a bunch of times is one-boxing. (Edit: this is because because trying to control the lottery number will just result in less games where the numbers are the same). However, if you're guaranteed a run where the numbers come up the same, then there's some hidden control, via the thought experiment itself. If I two box, Omega picked a composite, so in order for the scenario to have occurred at all (which by the thought experiment it's guaranteed to have) the lottery must have come up with a composite. Calling something random doesn't make it random. I probably wouldn't have noticed if I hadn't recently read GAZP vs GLUT.