I think OG needed more money to help the German police get evidence on CB.
It is very difficult even if you know someone is guilty of a crime to get the evidence to prove it. The phone call for one. It was a burner phone so if this person was in on it, this person is very unlikely to get in touch with the police, but without that person coming forward they can't place CB by the Ocean Club. Maybe others knew this persons phone number but I doubt it, if it was used just for the crimes it would be unlikely the number was shared.
The only way is to go over the witnesses statements and see if there is anything they can pursue. There must be people out there who know and are not speaking up. They were terrified of CB he carried a gun, whether that was for his own protection or to intimidate who knows.
I wonder if they could get DNA from the swim suits found in his van. Maybe finding out who those belonged to could give them more information on CB.
Running any police investigation costs a lot of money. But rarely, if ever has every penny of expenditure been grudged in the way it is and always has been for Madeleine McCann's investigation.
Bizarrely this prejudice predated the Home Office decision to fund Scotland Yard detectives when her parents were raising the money required to finance their own private investigators.
There have always been campaigns directed against any initiative on behalf of Madeleine McCann. In recognition that it takes money to keep an investigation going one of the most blatant wrecking procedures was sustained attack on that front.
When no-one else in the world was looking for her but her parents the vehicle used to finance that search was classed it as "The 'Fraudulent' Fund" by these seriously weird individuals. Seems apparent there have always been those who just do not want Madeleine found judging by their attacks on the only means of investigation.
Scotland Yard have requested further funding because there must have been justification to do so.
The Home Office have agreed to continue funding because they must have just cause for doing so.
Both SY and the HO are in full possession of the facts which justify their actions in doing so.