I understand your anxiety and fears on behalf of your daughter. Nevertheless, this sounds like an overreaction. Most injection drug users do not use the injection equipment pre-loaded with insulin for diabetics; and there is no obvious reason to asssume the diabetic user had other blood-borne infections. And even if the needle was in fact HIV contaminated, the risk of transmission probably was less than 1 in 1000.
Having said that, your daughter is obviously under the care of a provider--presumably her pediatrician--who ordered all the tests. That is where to go for answers to your questions. My quick assessment is that with the test results to date, there is no chance she has HIV. HCV also is low risk, but I have less knowledge about that possibility.
Good luck-- HHH, MD