Does this constitute a constructive discharge?

My husband worked for a small trucking company, he worked for this company for almost 4 years. For the last 3 1/2 years he has had one specific coal haul that he did. The only time that he did not haul this haul was if the pit was closed and then he would haul over the road. On a Friday in February he was scheduled to haul over the road, due to his usual pit being closed. On that morning as he was leaving the house he slipped on the ice and was unable to work. He did report off and provided a doctors excuse with a return date of the following Monday. When he took his excuse into the shop to give to HR he was told that he was taken off of his usual haul and placed over the road. My husband has never had an issue with attendance, so he was very upset by this decision.(His pit was not closed the following week, they placed someone else in this job). On Monday my husband did not go to work, he was contacted 3 times on Monday, asking if he quit his answer all three times was NO. The third and final call was from the VP of the company. By the end of the conversation the VP told my husband that if he ever called him "bud" again he would pop him in the nose. My husband applied for unemployment and it has been denied because they are saying that he quit without just cause. During the telephone hearing the HR director admitted that my husband was being punished for missing work on the preceding Friday that is why he was taken off of his usual haul. His usual haul has an income of about 45,000 dollars a year and the other haul that he was placed on has an income of about 30,000 dollars a year. Our next step is to get a lawyer and go to common pleas court. We asked for a review of the telephone hearing and it was denied. Is this something that we would be wasting our time and money to get a lawyer to go to court or would this be something that we have a chance at??