Accepted into Summer Residential Governor's School, didn't go...

I was accepted into the Summer Residential Governor’s School for math and science in Virginia during my junior year. I was unable to go because I decided to do another program I was accepted into that summer. Should I still list that I was at least accepted into the SRGS on college apps?

Probably not. People should only list things that they actually did on resumes/lists of accomplishments. Plus, you already have one summer program during that summer on your list, so you should be fine.