Under the guide tab next to the capture and loop buttons there is a button that looks vaguely like a galaxy which toggles "show in fits viewer". Would this help?
In the Indi Control panel, the tab for your guide camera, choose the Image Info tab. There is a checkbox down low, to your right (don't have it running, can not say exactly what it says). Uncheck it. Then guide images are no longer shown in Fits viewer.