If the breakdown was NOT caused by the renter,the owner will reimburse the renter for the unused dates as per section 4.3 of the Terms of Service.
In case the renter had to pay for repairs, he will be reimbursed by the owner for those payments.

If the breakdown was caused by the renter, the renter will be responsible for the repairs expenses as well as the costs incurred by the owner to collect his RV.
The renter will not be reimbursed for the unused dates.

In all cases, if the renter has selected RVezy roadside assistance, they will be able to claim some compensation included in the package.
To check what is included, you can check the following article:
What is RVezy Roadside Assistance?