Finally, in 1988, a chain of coincidence led Zwit to Hein's mother. She still lived in Sacramento, but she'd remarried and changed her last name.
The day he called her, she told him that Bob had received a posthumous medal for carrying one of his comrades to safety.
After that, Zwit went, in his words, a little bonkers. He vowed to find the families of the other seven dead soldiers.
He made call after call to the National Archives in pursuit of leads. He phoned newspapers in tiny towns, searching for obituaries. He narrowed one search with the help of a private investigator buddy who had access to a credit-check company.
One by one, he found the dead men's relatives. In West Virginia. Oklahoma. New York.
One by one, they thanked him, for giving them more details than what came in the curt government notification, for bringing what was lost briefly alive again.
"We got no personal belongings of Terry's back," one mother wrote him in a shaky hand, from Nashville, N.C. "Not even his glasses. He had worn them since 2nd grade and wore them all the time except when sleeping or bathing. I'm sure he died with them on his face ... I am sending a picture of Terry that I have cherished for years."
Only once did Zwit feel that his overture was unwelcome, and he understood.
And only one family's whereabouts eluded him. William Ward's.
'Can I help you find something?" the man asks.
But Lois Daniels has just seen the one name, the one out of the more than 58,000 names on the black wall, that she's looking for.
"William Ward," she murmurs.
She points her camera. The gleaming stone reflects the image of the big guy in blue jeans, with wispy faded blond hair, who has appeared beside her.
"Did I hear you right?" the man says. "Did you say, 'William Ward?' "
Does he say it before she stands up? After? When they tell it later, they won't remember it exactly the same.
But he has heard her right.
She says she grew up in the North Carolina countryside near Ward's family, is married to his cousin. She says Ward's mom and six younger siblings are still alive, though no longer on the North Carolina farm.
Two men who have come to the wall with Zwit today join them. One is the helicopter pilot who pulled Zwit out after the firefight. The other is Bob Gervasi, a platoon buddy who carried Ward's body away.
Soon, they're all hugging and, as Gervasi will say later, a little wet behind the eyeballs.