If i were just doing this in PHP/MySQL it would be easy, but I do not seem to understand how (if?) wpDataTable can do this.  You've tried to help, but I'm just not getting it.  I've therefore being editing this manually. I've been told it needs to work, or we need a new solution.

Here is the front table display: 

This display pulls from 2 tables, and displays Table 1.

Table 1 has id, from_date, to_date, empnum
Table 2 has id, empnum, fullname, ... (a lot of employee info)

We join tables on empnum and display the fullname name on our table above.

However, this is an oncall table, so now and then employees swap weeks.

On the front end, I need to be able to edit the table, get a drop down off all the "Employees" and select a new person... 

The fullname needs to show, but the empnum needs to be the value so that this updates the empnum in table 1, and on refresh pulls the new fullname from Table 2.

I'm sadly just not making the connection in the interface.