Taking @heckflosse processing as a base (really impressive in itself) , maybe you can further improve the look of your subject with wavelets:
LIZARD_SHARPENING-dc wv.png.out.pp3 (11.2 KB)
And you can always control the final sharpening with the global wavelets strength (if it looks oversharpened).
About the end of the tail, I’m afraid there’s no way to recover really unfocused areas, sorry.