Do you have a Nauticam housing? I thought that you had something else. Do Nauticam wet optics work with non-Nauticam housings?
I have a Nauticam housing for my Sony.
I used to shoot an Olympus OM-D E-M10 in a Meikon housing.
I was able to fit my Nauticam WWL-1 to the Meikon housing and use it with that before I got my Sony.
I don't know if I could have bought the adapter that I needed to connect the WWL-1 to the Meikon. Maybe. I didn't look.
The Meikon and the WWL-1 both had/have 67mm(?) threading. I was not able to screw the WWL-1 directly onto the Meikon housing and I can't remember for sure why, now. But, I know that what I did was take a cheap 67mm red filter that I had, which would screw onto the Meikon housing, and which had female threads on the front, to allow for stacking filters, and pop the filter glass (okay, polycarbonate) out, leaving an empty ring with male and female threads. I screwed the empty ring to the Meikon housing and then was able to screw the WWL-1 into that.