Finding vets: Tami, go to the Critical References section of
http://www.ferretcongress.org
and use the links to the places listing vets.  Each differs somewhat from
the others so you'll find an assortment.
 
Cauliflower ears: I think that this may have been covered in the past in
the FHL so it might pay to try to complete Archives of the FHL and the
Archives of the FML in case a vet reply was carried there:
http://fhl.sonic-weasel.org/
http://listserv.cuny.edu/archives/ferret-search.html
 
It sounds like the things you list can each result in trauma if extreme
enough.  If I recall right boxers get these from trauma.
 
Only two possible additions to a that very comprehensive list:
 
1. Be extra kind to yourself while you grieve.  If you made a mistake
(or someone else accidentally did) then forgive yourself (or that person)
so that everyone can constructively progress to learning from it to help
others.  That is what mistakes are for.  If you didn't make a mistake
(and most haven't done so) don't try to second guess what you did.  There
simply are things that you can't change and can't influence.  So, be kind
to yourself, do things that relax and make you happier.
 
2. Don't let someone else impose guilt upon you.  Cases vary and no one
knows long distance how ill the ferret you had was.
[Posted in FML issue 4049]