If her vent is smelling gross (as opposed to the poo that is in the coop), then yes, I would definitely want to rule out vent gleet. It can smell pretty gross and can make a bird fairly lethargic as it creates inflammation in the egg tract if it goes unchecked.
Just on the far chance that it might be vent gleet, I'll link a good site on how to treat it.
I had one hen that had minor vent gleet and responded very well to yogurt, probiotics, ACV in the water (after lots of yogurt first), and gently cleaning her up and spraying Tinactin spray on her vent, which was a bit red looking. I treated for about a week, and kept her on the yogurt for a week more and she looked great afterwards and has had no further trouble.