Longer than that.
Some of the calculations suggest a gravitational sink somewhere out there.
Some observations do to.
And to be honest, there are a lot of old legends about another planet that blows through the solar system on occasion. Nibru is the one that has become most popular these days, but Phoateon (Spelling?) was in the past.
Worlds in Collision, Immanuel Velikovsky, 1950, documents one that blew in and stuck around.
Phaeton, just like the car. Funny name for a car since it supposedly exploded.