Agree with Shawnie ... I had to temporary house my
betta in with my shrimp tank as I was moving around during my fumigation and during the 3 days my shrimp and betta were housed together I never saw the shrimp come out to play.
Sometimes I saw Melon nip at a shrimp but the shrimp were quicker - They were afraid

I felt terrible and as soon as I could I moved things to how they were and they were fine after that
I guess depending on the size of your tank and how good of a hiding space you provide will you test if the RCS will get eaten or not.