my colleague had once done this. the maid is also new to HK and has no idea with local law. but after be familiar with the local labor law, she sued my colleague who turn out gave the maid over hkd25k as compensation. the maid stayed with my colleague less than one year.
although you may have the forgery receipt of salary, hkd1.5k means a lot to these indoensian maid, they will do whatever to get the money back esp their labor union will back them up. it is not worthwhile to do this.