That would be a crime. Khalil was not charged with any crime. The only conceivable reason to not charge him at this point, is because there is no evidence of him committing a crime.

The admin doesn't have to charge him, they can just revoke his visa and deport him.

He passed out written Hezbollah materials. Like with their name, flag and logo on it.

He shouldn't go to jail, but he is no longer welcome in this country.

That's not providing material support. It's just speech.