I find he following answer to the question What's the soonest Oumuamua could return? unsatisfying and oversimplifying and the last five words "Therefore it will never return." unsupported at a minimum.

Oumuamua as an object is remarkable, because it has a positive net energy, which means it is not bound to the gravitational well of our sun. Therefore it will never return.

So I'd like to ask: *What natural mechanisms could lead to the unlikely case of a rogue asteroid or planet passing through our solar system twice?"

• Stick to accepted scientific facts and theories
• Let's give an ample time limit of 10 billion years between visits.
• For the purposes of this question, the solar system includes the Kuiper belt (50AU) but not the Oort cloud
• Don't include intervention by artificial means or intervention (divine or otherwise)