Was able to implement the idea pretty easily by adding this to Update of DungeonCameraControl, inside the if (this.overviewCamera.gameObject.activeInHierarchy && !DungeonManager.inMenu) using dnspy
```
if (Input.GetKeyDown(KeyCode.Q))
{
this.overviewCamera.RotateAround(this.overviewCamera.position, new Vector3(0f, 1f, 0f), 90f);
this.overviewFocusOffset = new Vector3(this.overviewFocusOffset.z, this.overviewFocusOffset.y, -this.overviewFocusOffset.x);
}
```
Seems to behave well through the different camera modes - doing the inverse with KeyCode E would allow rotating in both directions