Oh get a grip. Oh, wait, getting a grip is assault! PTSD, get out of my face with that bull. Talk to a veteran. My stepdad was in Vietnam for 4 years, tell him that getting groped by someone at a bar is on par with what he experienced.
Not a “grip” nowhere is the action described as a grip. To forcefully grab hold of another person’s private parts is assault. You and everyone has the right to determine the boundaries of physical contact with another person. When those boundaries are aggressively breached (so to say) the law is clear. It is wrong. When the aggression is sexual there are all kinds of descriptions in statute to describe the different degrees of assault.
Also nobody gets to decide what events are traumatic to another. We don’t know the personal history of this man and what factors made this event traumatic for him. I think determining a valid diagnosis of PTSD is best left to professionals. Is the term PTSD sometimes used to describe non medically diagnosed stress? Of course it is. And that should be made clear.
By the way thanks to your stepfather for his service.