Since he is accused of being such a prolific sex criminal, I guess that the Police may have suspected him but did not have enough evidence for arrest/search warrant.
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NewThoughts the time taken to proceed with this case made me think someone else might be involved.
These days, imho, I think it was probably PR. His mum says that she would rather die than learn that her son did this. This may be providing extra strong incentive for his ongoing denials.
The boots caught my eye. I know see that PR was a "cage fighting" martial arts enthusiast. Googling MMA boots I find that these (like boxer's boots) do look rather like the type worn by the person in the spiderweb video.
mma boots - Google Search