I whiled away the time today in the WT researching the above question on line. It seems to me that there is more evidence to say that the account simply depicts the poor nameless child/woman as being toast. The idea of her going into "tabernacle service" is completely fabricated and has no basis in scripture.
This to me is another example of bleaching and rinsing the murky bits of the bible to suit the purposes of those trying to suit the sensibilities of an audience. I have no idea if there was a Jephtha, if he had a daughter or if so what became of her. I am however very sure that the wise men of Brooklyn are no better informed than anyone else.
What say you?