laid-off and then fired

I volunteered for a permanent layoff around August 16,2002. My job was to pay me 26 weeks of sub-pay and I also would receive unemployment pay. My last day of work was to be Sept. 13. I called into work on Aug.30 and left a message to my supervisor that I would not be in for my shift at 3:30pm. I was also supposed to be at an unemployment meeting in the training room at 2:30pm on the same day. I showed up at the meeting and left at 3:10pm. When I showed up for work on Sept 3 I was told I had left my job while on the clock and I had to be let go. They called this voluntary resignation. We do not clock in and out and I feel that since I left 20 minutes before my shift began and my immediate supervisor knew I was not going to be at work, I should not have been fired. The employee handbook states" anytime an associate leaves the plant during work time without group leader or management authorization will be considered a voluntary resignation." I feel that since I had called in before my shift began I had authorization. The handbook also states"should it be necessary for you to leave your workstation duing your shift...you must notify your group leader." I had never reportd to my workstation. I do have a workers comp. claim against my former employer which I feel may have something to do with me getting fired. I have recently just begun to get unemployment benefits, which took 3 weeks for review. My former employer never answered the unemployment office's question as to the reason I was fired. Do I have a legitimate reason for a wrongful discharge case or an unfair dismissal?