The dog's role was to indicate areas where evidence might be found. I would think that anything found within that area would carry the scent to which the dog alerted, so there was nothing to be gained by asking him to screen those items individually.
"Might" being the operative word.
None was found.
Which didn't stop a certain ex-head-honcho PJ officer from making a mint out of his short-lived "investigation".
Whether he really did leave of his own volition or was booted with x-months's salary to find another job, he could have written a very different account of his time on the case, and it would still have been a bestseller.
If he had written a book that described the difficulties he'd faced (lack of computers, difficulties in back-up staff... generally gripes against slow procedures, the system in generall, I'd have found it more useful).
However, my objection is that's not what his book was about. And the book was fairly benign compared to the "docufiction", his column in whichever rag, plus innnumerable interviews, and whatever else he had planned. Ho
However, that's not what he did. He tried to convince everyone that she had indeed died in that flat and the parents (and others) had all been criminally involved, based on the flimsiest of "evidence".
In the meantime - and however remote the idea may be now (in 2021) that she could still be alive 14 years later - 1-2 years after her disappearance, or even later, there was nothing tangible to assert the contrary. The effect, for many, could (and probably was) that there was no longer any point in being vigilant concerning a child who might have been held captive).
He was effectively scuppering chances of her being found alive. What honest copper (and a dad, to boot), could be so heartless?