Maybe MH and TC shared a vehicle so he couldn't go looking. I can deal with that bit.
But once everyone is called up, including dad, knowing she is missing out of character and night is falling, how has not one friend or her dad gone out to drive that route? Maybe dad doesn't have a car either. But someone does. Why did they wait? Did they reason if she had an accident, someone would call. Otherwise there must be someone they thought she could be with that they couldn't reach, right?
Sunset was 6:19pm that day, so it sounds like they didn't become concerned until dark, thinking she could have stayed out all day and watched the sunset. But even in the dark, don't you go retrace steps?
You'd have to not have a car.
No one that is concerned enough to come help you, yet.
Or you have a reasonable idea where or why she isn't home.
Somehow dad found her after a very short while of searching at first light the next morning, after apparently rallying enough concerned people with cars to go look. I don't know if MH was there. Was he?
The circumstances of her being found have always felt weird to me. If they had just reported her missing, why weren't LE present at the search (or were they?)