My question involves labor and employment law for the state of: MN

I was just laid-off from my job after 6 months with the company. They have offered my 1 week of severance pay, however I believe that I am entitled to more.

The information packet they provided me with when I was laid-off outlines the following 2 scenarios for "Level F" employees.

1. If Level F and not Director, the minimum severance is 1 week.
2. If Level F and Director, the minimum severance is 3 months.

When I was laid-off I was Level F with the title Associate Media Director. I questioned why I was not getting 3 months of severance since I had a Director title and received this response:

"Because, under the guidelines your are not considered a 'Director'. Your title is 'Associate Director'. Based on your position and level, you are eligible for 1 week per year of service."

HR also refused to provide the guidelines they were referring to in the above response.

MY QUESTION: Do I have a case for 3 months of severance pay given that I had Director in my title?