If SY don't find Madeleine, then it wouldn't be because they haven't tried their best would it? They are exhausting every lead there is and are still investigating. All you seem to think about is the money being spent, when if it was your child or anyone connected to you it would be a different story. Even if SY were investigating the McCann's instead of abduction it would be a different story wouldn't it? As all you care about is getting back at the McCann's not finding Madeleine.
If SY don't find Madeleine it could be because their remit was to look for an abductor. If so, then they didn't fully investigate her disappearance and the money spent was wasted.
If it was my child I would be very upset if it was rumoured that the review I fought for wasn't investigating all possibilities. I would lobby SY to make their remit absolutely clear so as to squash the rumours once and for all.
Your opinions are based firmly on the assumption that the McCanns were correct when they insisted that Madeleine was abducted by a stranger. A lot of other people aren't convinced. I don't know who's right but I prefer my position of questioning everything to the position of those who spend all their time defending an unverified story; usually by suggesting what could have happened without any evidence or facts which support their imaginings. Often there is evidence or there are facts which actually contradict or cast serious doubt on these attempts.
The timeline is a good example of something which can be questioned. The PJ doubted it, but didn't research it further. Others such as Mark Williams-Thomas have mentioned that it wasn't verified. SY seem to have gone with the T9 version, although I can't see how they could verify it when they began to investigate the case without interviewing people in Portugal whom they don't seem to have interviewed.