If you are referring to the Insights Graphs app from the Homey community, I believe displaying the image directly from the Insights Graphs apps would be better in this case. I wrote up some instructions in the original post:
In theory, if the Advanced Virtual Device exposes the Insights Graph image like a camera, you should be able to use it with the Homey Image Viewer custom tile… I would need more information on how you have things configured and how the AVD device is exposing the image though… still, the alternative direct approach linked above is more streamlined