Cold Case OSINT

I have always been interested in "Unsolved Mysteries" and "Cold Case" files, but haven't watched any in a long time. Recently, while reading the book "Deep Dive" by Rae Baker, my curiosity for true crime and cold cases was peaked, so I decided to start watching some.
I was interested to see how the OSINT skills I have learned could possibly be used in various cold cases. I know that a lot of cold cases are eventually solved using new technology related fingerprints and DNA. Aside from that, I wanted to learn how OSINT techniques could possibly help in these cases as well.
There was a case that really blew my mind. In Cleveland, OH between the years of 2002-2004, a man had kidnapped 3 teenage girls at different times. He kept these girls in his home for an unbelievable 11 years! During those 11 years, these poor girls were subjected to unimaginable abuse. The suspect would leave the girls at home, locked up, while he went to his day job, as a bus driver for middle school children!
I began to ask myself, how could OSINT have helped locate these girls during those horrifying 11 years?
Facts
- The suspect knew the girls and mentioned his daughter, who they also knew, during his coercing them to come with him.
- The girls were alone in the house chained up with loud musing playing while the suspect was away.
- The suspect abused the girls to cause a miscarriage when they became pregnant
- The suspect eventually let one of the girls birth a child in the home.
- The child was a toddler at the time of their rescue
Questions
- What anomalies could have helped locate the girls during those 11 years?
- Could the fact that all three victims knew the kidnapper and his daughter have somehow helped put focus on the kidnapper?
- What type of OSINT search criteria could have been conducted in the local community that would have helped?
- 3 victims were abducted in the same town, during a 2 year period 2002-2004, how could OSINT have been used to look into their friends in common?
- would the two year time period increase the probability that the suspect was a local?
- How could OSINT techniques play a part in looking into the school friends of all three girls and their immediate families to look for any anomalies?
I will continue to research cold cases, because I am fascinated by the pieces of the puzzles. I also have great compassion for the many families seeking answers and closure for their loved ones. Each case gives a new perspective on events and how the clues are uncovered.