One possible solution would be to find a dictionary that has either pinyin or zhuyin fuhao to guide pronunciation. I believe zhongwen.com provides this.
In this case pinyin would have worked, since (afaik) it's a representation of Mandarin pronunciation, which happens to be the language they were speaking at the time.
However, (1) we don't have such a dictionary, and I think demanding such a specialized dictionary violates the argument in the OP; and (2) if they'd been speaking Shanghainese, which is her other Chinese tongue, or another dialect, pinyin wouldn't have helped.
I'm not familiar with zhuyin, but given what I understand about the problem, I imagine the same weakness would apply.
