Alter menu link if logged in
Instead of altering the menu link per role (which is tricky considering the process with which menus are built and cached), I would suggest you go for adding redirects per role.

The Url Redirect module should be able to help you achieve it.


  
  Url Redirect is a simple, flexible module for allowing user(s) / role(s) to redirect from one
  path to other.
  Url Redirect is also handy to add / edit / delete url(s) , specify role(s) / user(s) for url
  redirect, set a message for url redirect, enable / disable.