Exactly like many of us! We can't sleep so we get up and drive down Google roads, or actual roads for us local folks, look at maps, buy items of support, etcetera.
RD felt in his gut something just wasn't right. He has kids that play with Gannon and his sister (if I remember correctly). He lives right there on that street, in that neighborhood. He honestly has more of a vested interest than any of us and he wanted to be of service with the technology he had available to try and help. Who of us wouldn't do the same thing?
It seems in all situations we have to have a reasonable expectation of what is possible. Because LE has not inserted itself into the life of RD through warrents to search his house/vehicles, it seems highly unlikely that they consider him anything other than a neighbor with a big heart who just wanted to help a father find his son.