@edwardschris, Hi and along with Lisa, I want to welcome you to Mayo Clinic Connect. I want to let you know, that I do not have any experience with splenic cyst condition that you refer to. However I am going to share some things that I have experienced.

You said that your doctor found this during a CT of your abdomen and was not concerned. In my situation (with a transplanted kidney), local clinic mentioned a small kidney stone in my transplanted kidney in the written report. They were not concerned (I was being checked for unrelated issue). Months later, during my kidney check-up, my kidney team noticed it, and were concerned. According to them- for an ordinary kidney it would be no concern, however to a transplanted kidney it needed to be checked thoroughly. We are continuing to watch it, and no action at this time. I guess I share this because I am wondering if your doctor might be overlooking something of the importance, or if you perhaps have no other complicating condition.
I think that if you are not comfortable with what your doctor is/isn't telling you, you might get it checked by a specialist or at least get another opinion. But like I said, I have no experience with anything about the spleen. I wish I had more to share.
Rosemary