Maybe it was claudia waitinbg for a lift ?
The image is grainy but it looks like a larger male physique. I don't have the technology to 'clean up' cctv images but I suggest...surely the police have looked at this, since they would have access to the whole film rather than the small portion released to the public? He could have been waiting for a lift..or he could have been waiting for a.n. other to turn up and assist him in some way (remember, the male who walked round the back of Heworth Rd a few minutes later)...or he could be an unconnected person who happened to be walking in Heworth Rd at a crucial time. We may never know.