It takes a lot of alcohol. I learned to soak a paper towel and rub it on the sticky stuff with almost no pressure. If it sticks, there is not enough alcohol.
And change the paper towel frequently. It works by dissolving the sticky stuff, not mechanically wiping it off. So the paper towel picks up the dissolved crud after only a few wipes, then switch to a clean one.
I’ve cleaned cameras, mice, umbrella handles, and the back of a Samsung tablet this way.
I had some success in soaking gooey rubber parts in a vinegar and water bath overnight. It seemed to cause the gooey stuff to slough off enough that I was able to removed by scrubbing lightly with a dish rag.