Problem with second depended data validation list

Hi guys,

I have an issue with second dependent data validation list.
The thing is that I made a table with all tasks that are generated weekly. I have columns: "Task category", "Task", "Assigned to" and etc. Important are those first three. Also, I made dependence between first two columns with indirect formula in data validation, but I cannot find solution how to include dependence between first and third column, because I want to shorten list of all employees that I can assign to particular task category. I do not want option to select an employee who is not able to perform that task.

I hope that I was clear. I would be grateful if you have any suggestions or solutions...

Thanks...