Due to many legal issues too numerous to discuss here, you are playing with fire without a contract.
This industry is chock-full of people like yourself that trusted the vehicle owner by a handshake.
Spend sometime reading through the newbie section and you will see what I'm talking about...
Trump is not immune from prosecution in his 2020 election interference case, US appeals court says
https://apnews.com/article/trump-capitol-riot-presidential-immunity-appeal-46c2d7fc7807cd3262764d35e47f390e
First things first.... Get a contract spelling out what you are responsible for and what the van owner is responsible for.
After you have said contract then you can worry about all the rest.
You are an independent contractor, contracted to operate the vehicle for him. You do have a contract, dont you?
He could be, but not necessary. Does he find the load? Is he leased to another company?
Several factors are involved.
Inside Kevin McCarthy’s vengeance operation against the Republicans who fired him
https://www.politico.com/news/2024/02/01/kevin-mccarthy-vengeance-challengers-00138897
Due to the nature of expedite freight needing to go asap, you won't find alot of loads on load boards as the shipper usually doesn't want to wait for a board to work. May I suggest signing on with a carrier.
Trump legal news brief: Jury orders Trump to pay E. Jean Carroll $83.3 million in damages
https://news.yahoo.com/trump-legal-news-brief-jury-orders-trump-to-pay-e-jean-carroll-833-million-in-damages-220215022.html