

If your wondering isn’t critical to the thought I would simplify to “the monkey who might be able to see my ears” or “can possibly see my ears”. Otherwise AbouBenAdhem has the best option, though I might also suggest “The monkey whose ability to see my ears I’m wondering about”; splitting the prepositional phrase is more strictly proper but I think it reads a little better like this.
The best way to clean glasses is with your fingers using warm water and dish soap. Don’t use super hot water, it can damage the coatings on some lenses. Start with a rinse to remove any particles, then clean them between your fingers, then a final rinse, shake them off and let them air dry.
Using any type of cloth can cause scratches as you’ve found.