They really didn't need to - they knew their friends would decline 
Then it is wrong to claim that the Drs McCann refused to participate in a reconstruction, and saying so on a forum which deals only in factual claims which can be corroborated independently is also wrong.
If the reconstruction had taken place in May 2007 as a means of helping to find Madeleine I doubt if there would have been any dissent.
A year later, when the PJ had stated Madeleine was dead and her parents suspected of having a hand in that death, the situation had changed.
[Processo/16 - VOLUME XVIa.pdf P106 ]
Vol XVI p. 4237
xx xxxxxx xxxx
Exeter
Devon
xxx xxx
23rd April 2008
Re: Re-enactment of Events of 3/5/2008
Dear Stuart, Many thanks for your email, and for forwarding the reply from Senhor Rebelo. Also, thanks to you and your colleagues for arranging the re-interviews.
It is somewhat reassuring to see in writing from the PJ that there are "no suspicions over [us] regarding the commission of any criminal acts." However, we heard something similar in the weeks before Kate and Gerry were made arguidos! Additionally, the thrust of the PJ's closed questions during the re-interviews seemed only to focus on Kate and Gerry's culpability, suspicion about our written timeline or who involved the media.
After a year of lies, accusations and intrusion, I am sure that the Mr Rebelo can appreciate our complete revulsion at what Kate and Gerry have been forced to endure. Furthermore, we cannot help but feel that the re-interviews and re-enactment are all too little and far too late.
However, the last thing we would ever want is a standoff between us and the PJ, something that would only delight and benefit the press. Kate and Gerry desperately need the cloud of suspicion over them to be emphatically lifted, and the PJ need to complete their investigation. We also appreciate the legal obstacles to removing Kate and Gerry's arguido status, but would request that prior to us agreeing to the re-enactment the PJ:
• publicly dispels the damaging and disturbing lies churned out by the Portuguese press regarding alleged changes to statements, re-interviews or alleged lack of co-operation.
• publicly states there are "no suspicions over [us] regarding the commission of any criminal acts." This in no way compromises judicial secrecy. But without some official intervention on their part, a return for the re-enactment seems little more than a perfect opportunity for the press to speculate and libel us all once again.
We are very keen to help an investigation aiming to establish what's happened to Madeleine, but have no desire to assist one that seeks only to d**n our innocent friends. By actively restoring the focus on Madeleine and robustly dispelling the countless speculation, the PJ can expect our continued co- operation.
Yours sincerely,
Russell O'Brien & Jane Tanner
PS: We certainly do not request any specific reimbursement for travel or accommodation.