It may very well be able to get some of its food from the water itself, like microvert or other phytoplankton, it will also get scraps from the clownfish as well as the excrement from the clowns.
Better to try to feed it with a turkey baster from the list of foods that you have.
I wish I could see what you are seeing. If your anemone truly has major damage like a whole all the way through it, then I would suspect that it will decline very rapidly.
If however it seems normal now then I suspect either a simple deformity, or the mouth of it could be extended looking for food and you only think there is a hole in it, as in the mouth is gaping.
Without a pic its hard for me to tell.
Feed it, and let me know how it reacts.
Thomas