Meanwhile in the real world, the forensics neither disproved or proved what the dogs indicated. So it is clearly possible they indicated correctly.
We now know that 'Redwood of the Yard' does consider Madeleine died in the apartment.
Mutually exclusive events ?
Most certainly not.
As to Redwood's previous stances on the case, well let's consider the police get it wrong.
We have no evidence at all that the dogs alerted to a cadaver and in particular a cadaver of the missing child.
And we also know that DCI Redwood believes that Madeleine may have been abducted.
And we know that he has stated that the parents are not involved.
Mutually exclusive events?
You don't have any proof by the way that his stance has changed because there has always been the possibility that Madeleine died in the apartment or did not die in the apartment. As DCI Redwood has previously explained, she may be dead or alive.
Your assumption that there has been a change in his stance is just that, an assumption (or more curtly, a guess) because you have no proof of that claim.