Should the form used for "editing" a record always echo the fields which were in the form used for "adding" the same record?

I am designing a form for editing some employee records of an attendance marking system. In the system, when a manager is adding an employee, he has to assign the employee to a workgroup.

Later when editing the same employee, I thought not to include the workgroup selector because managing workgroups are done in a separate view.

I made the workgroup selector available in the "add employee" form to make the "add employee" flow easier for manager because then it reduces the risk of manager forgetting to add the new employee to a workgroup.

I assumed that manager will be navigating to workgroup section directly and do the task when he/she wants to remove or add an existing employee to another group.

So the questions I have regarding this are:

since we had the workgroup selector in "Add employee" form, will the users expect to edit workgroups at the "edit employee" form too?

Will the user's mental model be interrupted by having workgroup selector separated from the edit employee form?

Is there any conventions about echoing the same fields in edit mode which were available in add ?