Nishita was shot while guarding a KRON 4 News reporter in Oakland last week.
RELATED: Oakland police want to speak to witness with video connected to shooting of news security guard
Nishita's family says the video would help the family find closure and justice for Kevin.
"He was my everything," said Virginia Nishita, Kevin's wife. "We would watch a TV series and after awhile we would become the characters. He would call me, and he would call me the name from whatever series we were watching, just to make it fun. And we always had date night once a week."
RELATED: Former colleague remembers TV news security guard killed in armed robbery attempt in Oakland
Police are searching for a white 2004 to 2008 Acura TL.
There is a $32,000 reward for information leading to an arrest.
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