Rotating Camera About Mesh Coordinate System

Hey all, new to unreal and am at a loss here - working in C++. My camera is rotated 30 degrees relative to my root component/static mesh, as shown below:

The mesh coordinate system is in line with global. I need to have the camera rotate about the static mesh as the mouse moves (programmed to mouse X). However, just rotating about the camera yaw using something like:

FRotator DeltaRotation(0.f);
DeltaRotation.Yaw = Value * UGameplayStatics::GetWorldDeltaSeconds(this) * TurnRate;
SphereArm->AddLocalRotation(DeltaRotation, true);

where spherearm is the spring arm,

ends up rotating the camera down as well as around the static mesh. The goal is to have the camera rotate about the base mesh as I use the mouse, so that the spring arm would create an upside down cone after 360 degrees of rotation.

Ideally, I would like to just rotate the camera about the static mesh’s Z axis, but I can not seem to find a simple way to do this in C++. Anyone have any suggestions on an easy way to go about this? Thanks!