As the Otyugh is a weird creature, with a pair of eyes on a stalk and an aversion to light, one idea that came to mind was whether those eyes are actually anything normal. By 'normal', I mean whether they would be like an animal eye, with a similar lens, retina, etc. My line of thinking was continuing along with the idea that bits of the Otyugh are 'solid' in some way. A few themes could follow this; namely, whether the eyes are compound and also if they might be formed from blobs or clusters.
As you can see from my previous scribbles, I've suggested that there are blobby bits at the end of the eye stalk. If we zoom in on just this area, one concept was that the eyes are within the stalk and are made up up of several smaller solid sections:
You can see the aforementioned blobs, with nerve strands leading away down the stalk. Zoom in a tad more, and things start to look like this:
The picture above shows how the blobs are clustered within the left and right sides of the stalk, and I've included a side view of one blob. When I say 'blob', the idea was really more along the lines of them being solid in some way, and sensitive to light - but perhaps too much, hence their photophobia. One visual that fed into this design was the way things look when you slice a gooseberry in half:
|Note the veiny bits leading to the seeds|
Why a gooseberry? I dunno. Perhaps it's the way transluscent and solid mixes together. As I've said before, this mixing is how I imagine the Otyugh's overall look.
Anyway, another approach might be that the solid parts of the eye rest on the surface of the stalk. One interesting creature that uses minerals as the basis for a kind of eye is the chiton. Perhaps the Otyugh could have something similar, at least in the sense of those blobs being more like encrusted, light-sensitive primitive eyes formed from some sort of solid matter:
The scribble above maybe has things looking a little too conventional, but with the fourth drawing I was also thinking about the ways those solid bits might work as a single cluster.
This last scribble mixes the above concepts together:
The idea with this is to have a rough faceted look, either like coal or roughly worked flint. I've drawn an individual blob just to give some impression of the idea I'm trying to get across.
Still, I've not settled on a final look - although I tend to gravitate towards the look and feel of the last scribble. I also like the idea of the being able to see the nerve strands within the eye stalk. Maybe perhaps if the tip of the stalk was a little more opaque and was pigmented with various disgusting hues, it would help with camouflage when the Otyugh is hidden away...