A cell in InDesign is either Text or Graphic. Alternatively you can place images as anchored objects inside a cell. But in this way you can't have the image behind the text. So I assume that you have to build two tables here.
Is there a reason that this has to be a cell? You can do it with data merge if you have the image come in behind the text in a separate frame.
did you try with two anchored text frames and datamerge?
One text frame holding the variable for the image, the other one holding the variable for the text.
Sorry I ended up not doing this. So have no feedback as to if anything worked.