RCDC Join Group with Justification

Hi,

I would like to update the Group Edit RCDC to include two new fields (a Dropdown and Text Area). The dropdown would allow the end-user to select the business category (static list of values) and a text area where the user can enter his/her justification. 

In summary, I want to know if I captured everything properly from development efforts:

1. Create two new variables (dropdown and text area) and associate them to Group entity in FIM

2. Update the Group Edit RCDC for the user to enter the data 

I then want this information to be visible to the group's owner for the owner to approve and reject accordingly. 

I have done a number of development in FIM a long time ago and would like a refresher here. 

Thanks.