I think your only mistake is in the follow up, and easily corrected. Contact an elected state or local government representative as a constituent. They are typically more responsive. You did not make any mistakes on the road; if you rode in the gutter you'd have far more serious problems.

I had a bus driver run me off a 25 mph local road 3 times a few years ago (passed me incompletely, and pulled into stop before the end of the bus was past me); when was going to complain he said that I should know I am required to ride on the side walk (it's illegal) and swore at me when I asked for his name.

The local state representative was quite responsive; the bus authority responded quite quickly, and took the time to identify the driver, who turned out to be a new vacation replacement driver and not the usual driver. They seemed to think he should know traffic laws, and not use profanity with voters.

I suggest you contact your local city or state representative, preferably local enough to be familiar with the area, and ideally on a government body that funds the bus authority.