LE have mentioned a couple times they canvassed seeking CCTV, nothing specific. But as it’s now been over 4 years, I’d guess available CCTV obtained from anywhere hasn’t proven to be the smoking gun. In rural areas it’s often common for neighbours to keep an eye out for unusual activity when other property owners are away rather than utilizing alarm systems. Murder 101 for LE routinely is first investigating family members, then people with known associations to the scene of the crime. So considering the resources devoted to this investigation I’d be really surprised if every possible connection to nearby neighbouring properties hasn’t been thoroughly investigated. Although it took over two years for LE to place media emphasis on someone with knowledge of the Delphi area, for all we know LE didn’t take their eye off a likely close connection ever since day one.