Not seeing multi cams on Program Monitor, only Source Monitor

I'm not sure why, but the multicam icon on the Program Monitor is not showing the other cameras, but I am able to see them in the source monitor. My V1 track is selected/highlighted blue, and I've toggled the video tracks up and down, but still do not see the other cameras available in the Program Monitor no matter what I do. Can anyone help me with this? Thanks!
