Your description of tidal forces is incomplete. As given, it explains the high tide on the same side as the second body. One needs to consider centripetal force to explain the farside hightide. The combined forces cancel at the center of gravity of the moon-planet pair, which is why the two continue in orbit around the sun, but the balance tips when one leaves the center of gravity (which is usually inside the heavier planet in the direction of the moon) for the surface of the planet, favoring the moon’s gravity on the near side and the centripetal forces on the far side.

What I don't understand is why Io is not locked onto Jupiter the way the Moon is locked on to Earth (same side always facing us). Is it newly captured? Has anyone come up with an explanation of that??