I don't think Zeus will win unless there's bfr. Other wise this battle would last until Zeus is taken down or, Juggernaut quits, and walks away.
I do need to clear up the PIS when Thor negated Juggernauts forcefield. Ok this PIS wasn't the fact that Thor was able to negate Juggernauts field, it was the fact that he was able to hurt him. That was the only comic that ever implied that Juggernaut's durability derives from his magic shield. Now in any other comic Juggernaut was impervious to harm with or without the shield, and that is what made that moment PIS.
Also, Cyttorak is clearly stronger than Galactus. Trion Juggernaut proved that for us.
Edit: Juggernaut would lose in most cases though