For every action, there is an equal and opposite action. If Jupiter and Venus have enough gravity to impact Earth’s orbit, then Earth has enough gravity to impact Jupiter and Venus.
You miss the point. As a dyed in the wool accretionist, I suggest that gravity of orbital bodies attraction on earth is in constant flux but generally inadequate to effect orbital distances.
The article is suggesting that gravity is additive and the orbital positions of Venus and Jupiter increase the gravitational attraction on earth in a manner that produces change.
The effect of the earth gravity on Venus and Jupiter is in fact unknown but is not changed on the individual planets.