It was in a press conference a couple of weeks ago, Scotland yard said in an official statement that neither the McCann's or their friends were suspects or persons of interest. If you go to bbc it might still be on their site otherwise try YouTube.
The final report states that there was no evidence that either the McCann's or Murat practised any crime. It did not state the McCann's may be guilty at all.
For the umpteenth time, if Scotland Yard have suspicions about the the group, they are NOT going to publically say, yes, they are persons of interest. The same happend in Portugal in 2007. The police publicqlly said one week before they were made official suspects, that they were NOT persons of interest.
The final report did not say they are not guiilty, or may be guilty, no lawyer can state that, that is for a court and judges. but it did say by refusing to cooperate with the police by not going back to do a reconstruction, they lost the chance to prove their innocence!