Franchisee defamation actionable to national franchise?

I have a problem, perhaps you can render an opinion if it is pursuable.

On May 16th I went to pick up my paycheck from Liberty Tax service, a franchise operation owned by Wesley Talcott 3675 Nameoki Rd Granite City, IL. The Paycheck had had unexplained deductions of $140.00. I went to Mr. Talcott and inquired, he said he was recouping advances given at the beginning of employment, I explained to him that he had not paid me for the first 3 days of work and the advance he gave me was in lieu of an official paycheck, after investigation he agreed. I requested a new check and was told he didn't have enough money to pay me in full. On May 18 I delivered the keys and a written demand for monies due including deferred commissions in the amount of $750.00 which included my current unremited pay, I demand the payment for the Monday following payday and requested a check be mailed.

In addition to the unpaid monies I also worked allot of unpaid overtime for the benefit of the business and am wondering how to collect.

Finally the real reason I am writing since the above can be pursued through ILDOL, it has come to my attention that Mr. Talcott is slandering me to employees and customers with such statements as "Jon stole the social security numbers and records of all my clients before he left" and "Jon sabotaged the computers and now I can't make them work right".
I know this is slander, but, I do not know if it is actionable. Mr. Talcott apparently is not in a very good financial position, according to other employees he has requested them not to cash paychecks due to money concerns.

Normally I would think there could be no connection between Mr. Talcott and Liberty Tax Service since he is a sole proprietor only dba Liberty Tax Service, but, I have had trouble all along with Mr. Talcott's denigrating statements to myself and others and had previously decided to resign due to the verbal abuse, but, Lynn Owens of the Corporate office and Donna Halligan the Regional Manager of Liberty Tax service prevailed upon me to stay, leading to this unfortunate situation.

I have yet to file a complaint with ILDOL, I am also being required to have a hearing about my unemployment compensation this week due to statements made by Mr. Talcott. I am drawing from Missouri since my previous employment was there.

Given the above can you render me an opinion on courses of action including feasibility of a tort action?

Thanks
Jon Durrett