Apart from maybe Holly, who is denying his possible involvement ?
From my observations, Pathfinder is convinced Smithman is Gerry, as is BWFC, but certainly the latter seems to think the McCs may have employed CB to help with the body removal, though hasn't explained how they got in touch with him or when. Kizzy seems convinced he had nothing to do with it either as shes is 100% sure the McCanns dunnit, as is the resident WUM Spammy. G-Unit steadfastly refuses to express hardly any opinion at all, though she did once say abduction was virtually impossible and hasn't backtracked from that. Faithlilly seems open to the idea of his involvement, but her agenda has always been more about being judgmental about the McCanns and their supporters, and is now using CB's possible involvement in her twisted way to suggest that McCann supporters want Madeleine to have been raped and murdered. You don't really care either way, never have done, never will, you just enjoy having a laugh at everyone's expense.
Who else is there, really?