Sony 28mm f2 + fisheye converter

Hi, does anyone use this with Nauticam housing?

The port chart says to use N100-120 converter, extension ring 30, and 140mm dome. I have this exact set up for my other wide angle lens but when I put in 28mm F2 + fisheye converter combo I get vignetting on the outside.

Taking out the extension ring 30, with just N100-120 converter and 140mm dome, I am able to get no vignetting.

I'm curious if anyone else use this and can tell me if the port chart is just wrong, or if I'm missing something.

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For background, I took my gear to Mikomoto and Ito for the shark dives and did not realise I packed my Sony 90mm macro instead of my Canon 8-15+metabones+2x tele wide angle setup. In my defense they both had a black 3D printed zoom/focus ring on and somehow the 90 macro fits perfectly into the wide angle port urghhh. This 28mm F2 + fisheye combo was the only one that used the same ports and luckily I was able to pick up a used set in Tokyo for cheap. Curious to see how the quality compares - I would want the flexibility of the zoom setup for reef dives like Raja but I do hope the native lens combo has better auto focus for the shark dives... Took me until I was underwater in Ito shark scramble to realise... and even then I thought I messed up my zoom ring before I took it out and realised it was a macro lens... anyone else made such a silly mistake haha??