I really don't think that guy in the cobweb CCTV is PR. I know it keeps being dismissed here but the daily mail made a point of saying
"As part of their ongoing investigation, police arrested a 24-year-old man yesterday, thought he is not thought to be the man in the CCTV footage. "
CCTV probe in Libby Squire's disappearance after man caught on camera getting into car | Daily Mail Online
I DO however believe Libby was in PR's car, like his sister said, and there was an altercation which resulted in the neighbour hearing screams but at this moment I'm leaning more towards him leaving her at her house and either her returning to the bench and getting into the car with the CCTV guy, being abducted by someone else or wandering off on her own somewhere(like the Oak playing fields and that's why they don't have a specific place to search in the park but all over, guessing).
I know people here don't like hearing people say they don't believe he's guilty..sorry :/ He makes the perfect suspect though with the creeping/stealing/voyeurism and being one of the last people to see her.
I think they released that CCTV footage for a reason and that's to try and get that man to come forward to identify themselves and rules themselves out just because of the close proximity to where Libby was last seen. There could be numerous reasons why he isn't coming forward, maybe he's picking up a prostitute, maybe he was committing crimes that night, maybe he has a criminal record which would make the police suspicious that he could be involved or maybe he is actually someone who has abducted/hurt her. I just don't think it's PR.