in your situation, the IC or employee (if I understand the position you are referring to, I do not see the likelihood it is legal to consider those folks IC's), was asked to continue doing their normal work for a period of time. In the OP's situation, the work requested was not part of the original contract but even greater is the fact it appears that collectors must be licensed in Ga. If OP was an employee, they could most likely collect on their own companies accounts without any licensing but since OP is an independent contractor, they MUST be licensed (if it is truly a requirement in Ga) because he would be a 3rd party collector. An employee collecting on the company's accounts is a 1st party collector. A great deal of difference between those two and the requirements and abilities and liabilities of each of those.
You technically do not terminate the "person". Since an IC is essentially a one man company, you cancel whatever contract you have with them (the company). Now, you can have a contract where the contractee can assign job duties as they wish but they need to be careful because they border on the IC/employee line when they start playing with this. Once they start demanding too much control, they are not longer a IC/contractee relationship and they develop an employer/employee relationship very quickly and easily.They should've just called these guys in and terminated them. No discussion.

