Need advice ASAP, Company won't get me back to the yard.

I dont advise this for the OP but I dont have that kinda patience. If I would have told them I quit and they told me to pick up another load and go somewhere else..... especially with 8 stops...

Aint happening my friend, you can either authorize me to come back to the yard or you can send someone else after the truck. When I'm done.... I dont mean almost done... I mean: I... am... done. I'll bring it to you or you can send someone else after it.
I was respectful enough to let you know... I expect the same in return. Just get me home.

Again, let me be clear. I do not advise this for the OP here... Just my personality.

<----------

 

My opinion is:
Look this is a free country. Employment is at free will unless otherwise bound by a contract. They can't force you to work for them.. they can't prevent you from terminating your employment .
Youmay have signed an agreement when you signed all of your pre-employment paperwork agreeing that you wouldn't abandon the truck, but you've already offered to return the truck.
Unless there is some other agreement, they can't force you to pick up that other load..you have the at will right in this free county to terminate your employment at will.
They can't force you to work for them. They can't force you to continue you employment against your will.
If they threaten you by saying you must pick up that load and continue your employment or They will do something on your DAC to potentially harm you by damaging your ability to get future employment, that is holding you hostage by threat. They can not force you to work for them with threats.
They can use the agreement, if you signed one saying you wouldn't abandon the truck but, that's all. You've offered to take the truck back. They can't force you to pick up that other load.

If you have an attorney back home, I'd give him a call and ask him to make a call to you DM.. you'll be onyourway in a couple of hours.