It makes zero sense for a Business category to be the same as a Job category. Businesses are not categorized by the various job titles of their employees--this just doesn't work.
I would think you would want to make this change to your software so that it makes sense in the first place. Why not?
A business category could be Food/Restaurant, a job category for an employee at a restaurant could be anything from 'Finance/Accountant' to 'Service/Chef' to 'Administrative/Assistant'. Job category and Company category are not the same thing at all. They need to be separate things--especially to satisfy the primary purpose of your software.
I am telling you what we need the software to do.
We /need/ the software to provide Categories and Sub-Categories separately for Employers.
At this point there are three options:
1) you add the feature to your software--this would be easiest, since you already know your software
2) I add the feature to your software--this may take a while for me to figure out, hopefully you would at least assist me
3) I advise my client to choose different software since yours does not have the feature they need--this would mean a negative review