The Reflection Capture is not showing reflections for anything but the Sky Light when all Lighting is set to Fully Dynamic.
This was reported and tested in 4.24.1 (CL-10757647). This was reproduced in 4.23.1 (CL-9631420) and Main 4.25 (CL-10870012)
Results: Only the Sky Sphere reflection will be reflected in the chrome sphere, if everything is static and baked it's working.
Expected: For all reflections to show on the Sphere
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-86172 in the post.