Sorry to here that and read this post 2 days later.
if要醫館局打電話比僱主,then this maid is a higly infectious person (感染源頭), in that case, it is strongly believed that the maid has already known her TB condition right before she arrived.
There may have three possibilities:
1) the copy from the agent is a false one ( I heard that)
2) the maid did her medical exam long long time ago
3) the interpretation of the medical exam. is wrong (i guess this is the case in my former maid, whereas she had severe pneumonia from X-ray + wet coughing, but did not document on the report).
Strongly recommend the employer's whole family and any person has been contacted with this maid must take a medical check-up at once (X-ray at least) and note the symptoms in the coming three months. Take plenty of fluid, enough rest, and nutritious food, e.g. egg, fish and fruits particularly full of vit C. Make a thorough cleansing to the house, open all the windows, and if it is available, use a refresher machine.
Delay TB treatment has a long-run and severe effect!