No, you misunderstand. It was imo a brave, but necessary decision to have the twins tested a few months down the line, given all the mounting allegations. Had the parents known the tests would undoubtedly have shown positive, do you really believe they would have gone down that path instead of just leaving the blame for non-testing at the door of the disinterested PJ?
From Kate McCann's book:
On the night Madeleine was taken, you may remember, Gerry and I had been very concerned that Sean and Amelie had hardly moved in their cots, let alone woken up, despite the commotion in the apartment. Since Madeleine was snatched apparently without making a sound, we had always suspected that all three children might have been sedated by the abductor. We mentioned this to the police that night and several more times in the folowing weeks, but no testing of urine, blood or hair, which could have revealed the presence of drugs, had ever been done. Apparently, hair grows at a rate of approximately 1cm per month, so it was possible that hair samples taken even four months later could provide us with additional information. It was worth a shot, at least. I asked for samples of my own hair to be taken as well simply because I was fed up with the constant insinuations that I took tranquilizers, sleeping pills or any medication, for that matter. The process seemed to take ages and we all lost loads of hair. I couldn’t believe they had to take so much. The scientist cut chunks of it from Sean and Amelie’s heads while they were sleeping. I cried as I heard the scissors in their baby-blond hair. I felt angry that the children had to go through this further insult. As for me, I looked as if I had alopecia.Though I cursed the abductor and the PJ, I had bigger things to worry about. All the hair samples produced negative results. While this didn’t totally exclude the possibility that the children had been sedated, especialy given the time that had elapsed, it meant nobody else (including the PJ and the media) could prove otherwise. It also confirmed that I didn’t ‘abuse’ sedative medication. It is sad that we had to go to such lengths to demonstrate this; sadder still that such tests weren’t carried out at the time.