The Signs in the Silence - S6-E21
Stupidity: Bones realises she could pull a wisdom tooth from Amy in order to identify where she grew up and find her birth parents. Which works, but at no point do they consider simply going through missing person records with the relevant info. They know how old she is, they know roughly when she disappeared, not like there are hundreds of 3 year olds going missing every year, especially not with Waardenburg syndrome. By that age her deafness would have been apparent, which would narrow the pool hugely.
Answer: Answering my own question here but, having contacted various people involved in the production of Bones including Kathy Reichs, Hart Hanson, Eric Milligan, and Deirdre Lovegood who portrayed Taffet onscreen I finally have the answer. No-one know how she did it due to her constantly working alone. And she never revealed this information before her death.
Ssiscool ★