Unfortunately it’s not the incorrect performer credit that needs amending. It’s the correct conductor credit that needs amending. Removing the performer credit removes only the text on the display, not the image.
There are at least 3! combinations of conductor credits with Classical/Playing Now/Display and they are not consistently applied by roon. For example, the unwanted conductor image is not generated in playing now but is generated on an enabled display. I cannot imagine roon ever doing anything about this so if you don’t like the Jim Ed Norman image or any other image, just delete the credit. The OP has already acknowledged that the credits may be correct. It’s the image he doesn’t like.
It’s also not an isolated or edge case. Things are greatly improved compared with how they once were but roon has always had issues with image management. A related and extremely common image mishandling by roon is with Classical where, by contrast, most probably do want the conductor displayed. However, roon will routinely mismatch a conductor image with an image of the orchestra being conducted by an entirely different, often long dead conductor, with whom the orchestra happens to be historically associated. For example, a Simon Rattle image being displayed back-to-back with a Berlin Philharmonic image being conducted by von Karajan rather than Rattle.