The difference with your vape pen analogy was that that basketball player intentionally brought an illegal substance into the country thinking they could not be held responsible for it. This senator did an accidental thing that was reported to the authorities as soon as it was prudent to do so.
If your basketball player, of who we all know we're talking about, accidentally carried it into the border of Russia and then surrendered it to customs saying I brought this illegal substance accidentally I would be on the same side of showing a leniency to encourage this kind of voluntary surrender of contraband.
As would any reasonable person because getting people to voluntarily follow the rules is much better than doing it through force of terror which encourage this in them to hide the fact they are doing it such as your basketball player example did.