What two traffic laws was he arrest for?
The LEO states them both in the video. Watch it.
So it wasn't a warrant?
How the hell would I know? But a warrant was not necessary for an arrest as shown in the video.
It was 2 traffic laws? Did he refuse to sign?
Judging only by an obviously edited video, it appears he was arrested in lieu of being issued a citation to appear, therefore there would be nothing to sign.