It is quite simple blossom, he can't have what your husband hasn't got. He would be better making a claim on the Criminal Injuries Compensation Board rather than you directly. Link here:
http://www.cica.gov.uk/.
I do think you need legal help though.
My gut feeling is that £20k is far too high a quantum for loss of part of an ear - particular if his senses are unaffected and there is little cosmetic damage (after reconstruction). I assume there will be loss of earnings too though.
I also take the view that in civil law the provocation/contributary fault of the victim will be taken into account to reduce his damages.