Hiding Job Title or Other Fields from Requesters When Completing Tickets

We have been using the LDAP/AD feature for a while now. Unfortunately, the common AD attributes have caused a bit of a problem for us, as we now have employees who have moved since the last sync with the LDAP replica and their positions have changed one or two times over. I get a ticket from a different employee once a week complaining about this. I wish to stop it permanently, as I manage two SDP instances for different org functions and I have to change it for 100+ employees now two times over.

So, I have a question about two possible solutions:

Is it possible to export the requesters group, make the CSV file column for job title and department blank, and re-import them if they are imported from LDAP/AD?
Is there a way when people fill out requests to hide the field from the ticket templates and the AJAX auto-completion when typing in a requester name? The first part is obvious, the latter not so much.