[cypher]

It looks as though it could be from rubbing against something, spindle in the wheel possibly, are there any rough surfaces in the cage he might rub against when scent marking, do you see him rubbing against anything in particular when he scent marks? Any entrances or holes in anything that could be a bit small for him?
It doesn’t look like any kind of mite issue so cleaning won’t help, doesn’t look like the start of Cushing’s either so rubbing seems like the most likely cause to me.
I wouldn’t give him coconut oil,try evening primrose oil .