Hi,
BO IAMUsrListController is a controller object, which is only used by application and not exposed for external use, it's PSM status is also not released, there won't by any other object like webservice built on such controller object, so you cannot use this BO.
May be you will have to check if IDENTITY BO provides such information, or contact application team to check if it is exposed.
Thanks, Pradeep.