1st of all, sir, you acted very graciously. You didn't cuss out the truck driver. You probably saved him his job, because had his company found out about his poor driving (had he hit you)...the poor guy would probably be fired.
2nd, using a dashcam like that saves lots of "he said, she said" in case you got into an accident. No ambiguity, but can be a double edge sword if you're indeed at fault...But if you were at fault...you wouldn't mention the dash cam
3rd, no one was hurt.
Good job my man!