I think it would be very odd indeed for the parent of a missing child to cooperate with the police in an investigation designed to send them to jail.
In Kate's book the 'tosser' episode describes Kate's realisation that the PJ were out to get her meaning that no-one was actually investigating her child's disappearance and she had become 'the investigation'.
This gave her added strength because of the realisation that without her and Gerry Madeleine was not being looked for ... and as events have proved in retrospect that is exactly what happened ... until the police reviews of 2011 they and therefore Madeleine were on their own.
The McCanns didn't like being investigated by cops which they clearly thought were unintelligent and stupid. I know who my money is on.
For davel's benefit, the book was nothing more than an attempt to point the blame anywhere except at her own door. Poor me comes across in every page I have read. That fcuking tosser Ricardo Paiva, Tweedledee and Tweedledum were incompetent.