They went for the previously speculated 30 mm extension on a dome port for the Pana 8 mm fisheye.
Undoubtly the Nauticam 4,33 mini dome with the 30 mm mini extension should also work.
This does "work", but there is vignetting from the lens shades at the top and bottom of the 4:3 frame, so it won't be the recommended option.
The official recommendation for Olympus 8mm f/1.8 Pro will likely be 36048 140mm Glass Dome + a new 17mm extension, but these options are undergoing ongoing testing.
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