Question about OWI, insurance, and employment?

I live in madison, WI. I recieved an owi in 2005. I recently applied for a job with a landscaping company. I don't have a personal vehicle. This last week I had my liscence reinstated in full, no restrictions, no sr22 insurance required. I was told I could start immedieately, and to come in tommorow. The employer called me back today, to tell me not to come in until he can verify that thier insurance carrier will be able to cover me. I really need this job. Is there any reasons why I should run into trouble with these cirstances?