The Sphere Reflection Capture does the same thing for my scene. Everything was working great in 4.11.2 (no static lights showing up in reflections). Once we moved to 4.12.5, that’s when the issue occurred.
It also baffles me that your scene works great and like how it’s suppose to look, yet my scene is having the issues. If Sphere Reflection Captures would fix the issue, I would switch to them in a heartbeat.