I don't think you are right in assuming that the "cut-off grade...

I don't think you are right in assuming that the "cut-off grade resources relationship" can be directly linked to dilution grade.

The resource report is not clear about the construction method of the wireframes which contain the resources except to say that only composites which fell within a wireframe could be used in the estimation of the grade of the wireframe. The wireframes could have been constructed from composites defined by a cut-off or by geology, it doesn't say. The resources reported by cut-off grade only include stuff within the wireframes hence the high grade resource varies little with changing cut-off.

The stuff which might be dilution is largely outside the wireframes and you can't know what grade it is.