In 2010, Amber, a sex worker, had an encounter with a man at her home ... he was paying for a lap dance. Shortly after he arrived, Amber called Dave, telling him the man was trying to rape her.
Dave quickly returned home, walked in the door, and says he saw a giant of a man -- around 6'5" -- standing ominously in the living room. Dave told him to leave, and the guy refused. Dave ended up grabbing the guy, trying to get him out, and a fight ensued.
Eventually, the guy left in what Dave says was either a green or black Chevy Avalanche.
A month later, Amber had an appointment with a man and never returned home. The second she went missing, Dave knew it was the same man who was there a month earlier. Dave says Amber needed the money so she took a fatal chance.
After Amber's body was found, Dave was interviewed by police and told them the story, describing the man in great detail, "right down to his beady-ass eyes." He followed up 2 more times with cops, but they never chased down the lead.
Had cops run registrations for anyone in Long Island who had a green or black Avalanche, they could have then looked at the driver's licenses of the registered owners and they would have found a 6'5" man who fit Dave's description to a tee. That man was Rex Heuermann, and the Avalance was routinely parked in his driveway.