Freeze isnt an on/off switch but a continuum.

Berzerking may be fighting with enough opiates in you that you don't feel, and your forebrain so frozen that you no longer have access to moral judgment. Fighters who berzerk have higher incidence of PTSzd than fighters who don't. (Jonathan Shay, MD, psychiatrist and VN veteran.)

Acting on ones own behalf can be protective against PTSD. Among the children in the Chowchilla bus incident, the boys who acted to rescue themselves and the others had fewer /less severe symptoms later. (Lenore Terr, PhD, psychologist and research).

My PTSD mentors have all told me that it is better to do the wrong thing than to do nothing. Of course, I Believe freezing once saved my friends a beating but who is to say PTSD is not a worse beating than you get in a fight.