InfoPath Dev

First time so go easy: I created an IP Form to enter data in SP List B. Both SharePoint List A and B contain the same unique column, MEMBER ID. The user will enter the MEMBER ID and query both lists A and B. Basically, List A contains the data set they need to review and take action on. List B will contain the action they took on that item via a drop down and a small text box. The users may work an item multiple times as List A will be refreshed monthly. List A is already over 5000 and List B will also be above 5000. I have entered MEMBER ID =“0001” and pull back data from List A and changed a drop down to “Active” and added a note via the NEWIF form and saved it. When I open the NEWIF form again and QUERRY it pulls back the same setup data from LIST A and the “ACTIVE” & note previously added. When I change to the drop down to “Terminated” and click save, I get the Member ID cannot contain duplicate ID. However, if I go into LIST B and open in edit mode, make the change, and save, it updates, which it should. However, I nor my client wants their users having to switch between the NEWIF form to search the list to make updates. How would I create a rule that would switch the InfoPath form displayed to the user from the NEWIF to the EDITIF form based if my List B query string is NOT NULL?

 Ok, I have learned a lot about SharePoint 2013 in the last week to know that I need to refine this: 

 

The solution to this issue lies in firing the EDITIF.ASPX when the Query to LIST B is NOT NULL and pass the ID from the query return data to the EDITIF.ASPX to create the necessary correlation.

 

Is this done in the jquery?  if so which one and how and where do I change it.  I now have  Visual Studio loaded but do not have farm access.