Hey folks, it looks like Retool doesn't support icons in table column at the moment though that's something coming in the future!
Clickable images in tables can be a bit tricky. You can set up an event handler on your table that runs on row clicks and then check for the column of the selected cell, this may not be the best workaround but it's one way to get things going:
Let me know if that works! I've included a JSON you can import and play around with 
clickable_image_column (1).json