head lump seemingly untreatable

Question
wondering if perhaps you can help even though my friend may not be around when i receive a answer.

she is 2.5 years  has bumblefoot, has had a mammary tumor removed ( at about 1.5 years)  

for almost 4 weeks now my rat has had a series of trips to my exotic pet vet for a growth on the side of her head.

the first trip it was lanced, checked for cancer (given the all clear) so she was given 2 drugs to take ( i was away so i am unsure of what they were)  and it cleared up but then came back again 9 days later.

she then went back to the doctor and a sample was taken and came back that it was a highly resistant strain of infection and should respond to bactrim.  it did not and continued to grow so we went back but was no longer only soft and squishy it had a hardness to it.
a sample of the new tissue growing ( at the base of the ear) was sent to have a histopath test. she was given a mixture of baytril and bactrim until the results came back.

it came back negative of cancer but we were still thinking that it could be and there just wasn't enough tissue given for it to be confirmed.   so a decision was made try to freeze the area to stop the infection...
As she was opened this time there was no longer any infection now it was white tissue,  it was partially cut away and the remaining tissue was frozen. this was maybe two weeks ago

our hope was in vain it just grew back quicker. my vet and i have run out of ideas.    the lump is now the size of a small rubber bouncing ball that you play with as a child (about 1.5 cm) it now has again the squishy texture of an abscess but i am not sure i should put her under anesthetic again because she is now wheezing when she drinks or gets excited.

she is still eating. it is starting to affect her breathing she wheezes  and breathes more rapidly than usual.  

i just would like to know if you believe there is anything else i can or could have done.  i know she is old and that it is just a matter of time but she is my best friend and i would give anything so make her happy and healthy.  

Answer
Oh my that is really a story.  Do you have photos?  I know a great person that can assist me in this but she would want photos for sure.

Email me at askcritterkeeper@yahoo.com as soon as you have photos. I would take them from all angles if possible.

What color is it? Is it smooth or lumpy? Has there ever been an odor?
WHen you say "side of head" do you mean literally the side of her head, like behind the ear, or more on the face?  
I guess thats why photos are best.  

Please let me know right away.


hang in there.....

Sandy