Right, fellow Sleuthers, something very surprising has just happened to me. I contacted the Met Crime Centre on twitter last night, with the timestamped footage of the Poynders Road/Kings Ave CCTV at 21:30 showing the two individuals, with the dog and/or shopping bag, just in case they had missed it. Totally unexpectedly, I've had a call this afternoon (assume twitter has my number saved) from an officer from Putney Police, who asked me to point him in the direction of the TFL traffic jam archive-
London Traffic Cameras - Live TfL JamCam Feeds
I was very taken aback to be contacted by an officer regarding this investigation, so I would urge all of you to contact the Met Contact Centre on twitter @MetCC with any of the information you have gathered. Something I considered basic to the investigation, like looking at CCTV cameras has ended up with a call from an officer asking how to access the archive itself.
N.B. I'm aware this anonymous post from a new member about being contacted by a member of the force can arouse much suspicion and scepticism about the legitimacy of this, but all I can say is I'm not looking for clout, just to urge all of you (in the UK) to get in touch with either the anonymous tipline or the Met Contact Centre with any information on the threads that you think is important