Thanks for visiting HCM.
nodes are the second most common site for tuberculosis
FNAC report is highly suggestive of tuberculosis as there is granulomatous inflammation with langhans giant cells which are usually found in tubercular lesion..moreover histopathological diagnosis (FNAC) is superior to quantiferon TB gold test.
Considering the laboratory report and prevailing source of infection in the form of you, your mother must be considered a case of tuberculosis, and in my opinion should be treated with ATT.
It is said that in tuberculosis, if you suspect, always go for treatment....
And at last please continue your own treatment for the prescribed duration i.e 6 months..