Hi K.---Did some checking on the internet to see what this cyst is like. It looks like that ultimately surgery is the best choice, if you want to have the cyst gone. And trust me, I am one who would look at medical intervention as a last resort. When there are 'mechanical/structural' issues with the body, then physical intervention is usually required.
Please do not worry about your little one going through this procedure. Although no mom wants to see their child go through surgery, kids are extremely resiliant. My first, my little girl, had surgery to correct crossed eyes at 7 months of age. By 4, she had had at least one set of tubes and at least one more surgery on her eyes. You gotta do what you gotta do.
In the meantime, you can always make sure the family is eating an optimal diet, one that consists mostly (80-90% of calories) of plants. Getting all of the nutrients, vitamins, minerals and antioxidants, found in those plants would give his body the building blocks necessary to do any healing or prevention of infection on its own. Try to eat a rainbow. Every fruit and veggie has common vitamins in minerals, although in different ratios, but the colors are what is important. The colors indicate the different antioxidants that are available in those foods---lycopene in red, for example. You get your flavanoids from dark colors, berries and wine/red and purple grapes and dark chocolate. Let me know if you would like any more info on this subject.
Good luck with everything...and don't worry. D.