Mike T noted the DB listing for I.Q. DUDETTES here ignores her, but it appears she's listed there after all, only under the Chinese version of her name along with it's English transliteration. I would have posted these last night, especially after "Oi-Lin" started sounding remarkably like "Irene" the more ways I said it, but my home internet crapped out and I spent several fruitless hours on the phone trying to reset things, when I should have just waited for the network to come back on line today! 
http://hkmdb.com/db/people/view.mhtml?i ... y_set=big5
Here's her other listing in the DB, under her proper English name:
http://hkmdb.com/db/people/view.mhtml?i ... ay_set=eng
And finally, here's a screencap from the movie verifying it is indeed her (top row, middle name in Chinese). Looks like somebody simply sounded out her Chinese name and forgot to add her more common English name. Sorry for the so-so quality of this. It's taken from a VCD, but hopefully it's enough to merge her listings here
I'm thinking Irene...etc. should be the main name, Sin Oi-Lin an alias.
Not surprisingly, the IMDB actually has two entries for Ms. Santiago as well, placing both of them in DUDETTES. Girl needs a better agent!
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