The film appears to be too grainy to make a positive identification. Blowing the same image onto a screen does not make it more clear. We know that a man about the same height as VT, wearing a longer dark coat, was in the grocery store black and white surveillance footage when Joanna was buying her pizza or cider. That person appears to abandon his shopping cart and return to it, or not - depending on what footage you see.
It cannot be conclusively proven that VT was in the grocery store at the same time as VT. What is his timeline? Wasn't he speaking with the landlord at 7:15, then in his flat (?) - coming home from work (7?), then out taking pictures ... if he saw Joanna at some point, it was most likely closer to home, but perhaps not. Fortunately it wasn't needed for a conviction.
What difference does it really make? Is it a point to suggest that police didn't do their jobs? They did ... and prosecutors too. They did their job and VT was convicted for life with 20 years before parole elligibility ... without the snuff flicks or footage of what he may have been doing prior to the murder.
If we had a link to the grocery store footage, took a print screen, put it next to the shot of him standing outside his flat while the media was filming ... we could compare the two. Do you have the two links handy?