I agree with the posters above..
and as to the wound itself .. If it was mine old leg I would do
what my grandma did when I was a kid and i would come home
with all kinds of cuts and things.. in times when people did
not even heard of using antibiotics on everything possible..
she would just run to the nearest grocery store, buy a little
bottle of purest alcohole she could find (not the rubbing yacky one)
but vodka / scotch.. clear alcohol type of thing..
and she would pour it on the cut every so often ( few times during
first three days) first time would always be the most painfull and
then somehow less. and less.. and once the wound healed there was no pain anymore..
she did it probably to kill off any bacteria.. that was desinfecting kid of a choice that she learned
from her mother who saw doctors doing it all the time.... go figure..
how safe it is or was? I don't know but clearly I never
had any infections and my wounds never got any redness around
so it probably did the trick..
this is not my advise though as I am not a doctor, it is just
sharing my own experience from curious times and places of my past..
I think in your case what is very important is osmehow to protect the
wound from secondary infection by touching or accidental rubbing against
shoe or whatever..
yet it is tricky from the position point of view..
and also because oxygen heals woonds fastest.. and cutting it off could
lead to T.. in itself.. as in putting some bandaid that would be non-breathing kind.
I really don't like them...
if you were to put something on her foot make sure it is BREATHABLE
CLOATH band aid as opposed to plastic ones that are just sort of
tape scotch material..
change it often.. really often and keep the wound open for a while to
air.. half hour to hour or so if possible doing nothing else.. watching tv..
or stuff as not to risk walking without anythign.. this will the oxygen to get in and help to heal the woond
it is available in stores just one has to look for it... it is mixed up with bad guys.
also..chances of getting T.. is most dangeorous if the cut was done on rusty things or
things that contained feces material otherwise supposed to be not that
dangerous.. but then again need to be researched further...
oh.. lastly I probably would go with topical antibiotic.. neosporine or something just in case..
amd also blueberries by tons!.. eat fresh blueberreis.. juice them
organic at best.. and wilde frozen ones..
super booster to immune system that she needs.. and what a delicous
way to get better

Good luck! and keep us posted.