Then I guess we'll see another one soon (unless we freak them out by noticing them and broadcasting about it!).

Once more survey telescopes like Nancy Grace Roman and Xuntian come online we'll increasingly find out how many there really are and I suppose if they seem to like buzzing the proverbial tower.

In fact, we already have; that's why there's a 3 in its name.

The other two didn't make a planetary close pass. As we see more of them, the statistical strangeness of the third one getting so close to Mars will fade. (Or, I suppose, they keep doing it and then we really will have a puzzle on our hands!)