Jupiter was slowed down and lost orbital energy to V2, which gained it.

Having lost energy, Jupiter fell (slightly) closer to the sun and was accellerated by its descent through the Sun's gravity well.

To return it to its original position you must add energy and it will then move out and decelerate as it climbs the Sun's gravity well.

This is a 3-body problem, not 2, and we have a gravitational gradient to complicate things!

(BTW, V2, having gained energy, moved outwards through the Sun's gravity well AND SLOWED DOWN -= go look at that graph again and see all the concave listric curves of velocity vs AU)