I went snorkling off the shore of Kenya 2 years ago.

On the reef I saw this octo. it was about the size of a O. vulgaris.
I was just curious about what species it might be.

I took a pic, but unfortunately, it was very and I mean VERY unclear.

There's O.Vulgaris, Macropus,Cyaenea and Aegina

So you could have seen a vulgaris.