The Vulnerable Adults Investigations Unit of the South Carolina Law Enforcement Division, created pursuant to Section 23-3-810, shall, in addition to its investigation responsibilities under that section or Article 1, investigate cases of vulnerable adult fatalities in facilities operated or contracted for operation by the Department of Mental Health or the Department of Disabilities and Special Needs. Provided, that in a nursing home, as defined in Section 44-7-130, contracted for operation by the Department of Mental Health, the Vulnerable Adults Investigations Unit shall investigate those fatalities for which there is suspicion that the vulnerable adult died as a result of abuse or neglect, the death is suspicious in nature, or the death is referred by a coroner or medical examiner as provided in Section 43-35-35(A).