Another way of enclosing the images as image fil in a cell, then displaying those images at or closer to full scale is to place a second table, consisting of one cell (or more) of the size you want the image to be for viewing purposes.
Expanding the image then becomes a Copy and Paste process:

The main table is the one on the left, containing the 'bill image' as background fill in cell E2. The (larger) single cell table on the right is the 'Viewing table,' wher the image will be placed for viewing.
Select Cell E2 with a single clock, then press option-command-C to copy the cell's format settings, including Image Fill, and the image used in that fill.
The select cell A1 of the single cell table (single click), and press option-command-V to paste the copied format into that cell. For the image above, the result is shown below:

To remove the image from the 'Viewing Table,' Select and copy the format settings of any cell that has been set to No Fill, then Paste that format into the Viewing Table cell. using the same option-commnd-C and option-command-V keystroke combinations as above..
Regards,
Barry
PS: consider adding a second cell to the viewing table, set to have No Fill, to provide a convenient fixed location from which to copy this setting to be pasted into A1 to clear it.
B.