Local A&P said your paint shop can fill w METAL SET A4 ALUMINUM FILLED EPOXY ADHESIVE and you will never know. Take a space halfway between original holes and put two new rivets in.
METAL SET A4 ALUMINUM FILLED EPOXY ADHESIVE sold at aircraft spruce.
This stuff is good if you are planning to polish but structural epoxy is a little better if you are planning to paint. Flatten the dimple, drill if cracks develop (don't flatten or drill the underlying structure), and install with a dab of epoxy between the structure and the skin. Remove excess and rivet the holes closest to the fix before it sets. Extra rivets as mentioned in other posts are a good idea. If surface is not completely filled, add a little extra epoxy. Finish riveting. When the epoxy is set, carefully file the fill down to the surface - this step can wait until you are ready to prime for painting so any scratches can be filled.
If you are trying to preserve your dimple pattern in a painted surface, take a piece of metal tubing with an inner diameter close to the diameter of the rivet and sharpen the circumference at one end (bevel toward the inside). While the epoxy is not wholly cured, press the tubing into it, leaving an impression that will mimic a rivet.
A similar technique can be used for countersinks that are too deep, simply fill them, flush the top and bottom surfaces of the hole, re-drill, and re-countersink. A rivet or dimpled piece will hold the fill in place and the fill will take the compression loads of setting the rivet without deforming.
Caveat: Both of these techniques are suitable for fixing a
single, isolated oops. But multiple errors should be cause for replacement.