Unfortunately, even if the Sheriffs Office has a Mental Health Investigative Unit (where peace officers receive specific mental health training) they are only charged to investigate cases concerning emotionally disturbed persons through the collection of evidence and witness statements in addition to courtroom testimony. There was nothing stated that we know of by family or those Officers that viewed the video(s) that he was displaying any mental health issue markers.
Code of Criminal Procedure Chapter 6, Art. 6.06. Peace Officer to Prevent Injury Whenever, in the presence of a peace officer, or within his view, one person is about to commit an offense against the person or property of another, including the person or property of his spouse, or injure himself, it is his duty to prevent it; and, for this purpose the peace officer may summon any number of the citizens of his county to his aid. The peace officer must use the amount of force necessary to prevent the commission of the offense, and no greater.
An Emergency Apprehension and Detention (A&D) only occurs when an emotionally disturbed individual is unable to make treatment decisions regarding their mental health, no safe alternatives are available for the individual, and the individual has done something that tends to confirm the likelihood of serious harm to themselves or others.