I am not sure as to whether you are new to HK, but I have been living
here for many years. I too have had such problems with the countless
out-sourced domestic help that I have had over the years.
It took me some time to work out why there were so many geckos around my
maids rooms- and I learnt whilst holidaying on the islands of the
Philipinnes, that Filipinas believe that the Gecko is a fertility god
and they diliberately feed them with candies and food to make sure that
when they get holiday leave (which i totally disagree in paying for, but
that is a seperate issue), they can go home to their husbands and
concieve ( more money from me!!).
Gecko urine is as poisonous as cyanide, and there have been many cases
of gross negligence in Hong Kong involving Filipinas, Geckos and expat
children!
If passive resistance does not work, try squeezing the fridge into her
room, a tactic that many expat wives have employed over the years to
help solve their out-sourced domestic help issues.
Good luck, and remember-the Filipina for "yes" (or-or) is the same as
"whatever (or-or)!