The question about the apparent desire of some of the Pitcairn men to have sex with children, and whether this is cultrally acceptable if everyone involved agrees, does not matter here. Some Pitcairn women have said sex witgh 12 year olds is normal in their culture. However, the women involved in the allegations have made complaints to the police (even if some others haven't). So, there is a moral case to answer. Some children claim to have been raped by older males, in some cases older adult men. These are Pitcairn women who are making complaints.
The island appears to be some kind of dysfunctional family where some seem to decide to find their sexual relief in the rape of children.
I'd be disappointed if people were to argue that, in some way, this should be accepted.