I think this, from the GNR report, pretty much confirms my view that the GNR officers didn't have the right type of dogs at their disposal:
On 7th May the same searches were continued, being extended to to the entire northern part of Almadena to the site of Espojeiro and the verges of the EN125 until the Boi valley.
At about 19.. the undersigned officer, accompanied by the Commander, Officer Silva, took part in a meetings with the PJ Directorate, being asked by the PJ about the viability of giving the girl's clothes to the dogs for the dogs to sniff again, and if by means of the odour inhaled, they would be able to mark an identical odour in one of the resort apartments even though its door was closed.
With regard to this task, Officer Silva referred to the fact that the time that had passed would be a crucial condition for the dogs' work in obtaining results and that the entirety of the human odours existing in the apartments and access paths could make the dogs' searches very difficult. However, in spite of not being a normal situation for tracking, it could be attempted, whilst the operation should be carried out as quickly as possible and not directed towards one but to all the apartments in the resort, it being appropriate for the handler not to know which apartment was chosen, so as not the be conditioned.
Note, also, the reference in the quote to the possibility of bias distorting a handler's judgment and precaution against that.
Then think of Grime and those 'Madeleine' stickers on the back of the Renault.
I think the Portuguese dog handlers were much more professional than Grime ...