Ah yes, ignoring the size of the eyeball, I have two recommendations, one I forgot to mention just now. The first is the one I mentioned in my previous comment just now, I suggest that you should measure the angle you used to find the length again (I got 10 degrees, you got 35, so unless you were using the upper boundaries to find the width and not the width of the exposed sea floor, the degree should be significantly less than 35, this will upgrade the results).
The second is that you should consider a 0.25 second timeframe, at least as a high-end. Sage Centipede has no idea what happened, even though he saw Saitama run up to EOW and was watching when the feat occurred, plus since the movement occurred between panels it could be pretty quick.