Yes. If your maid no need to extend that means no need to fill in ID91.
OEC form = Overseas Employment Certificate, your maid must fill in another form from Philippines Consulate first with her personal information and have her signature and need to pay HK$32 to get the OEC form, whe she come back to HK after vacation she need to present this form to Philippines Immigration Dept (Airport).
Witness: Everybody can sign
Contract Date: I fill in the date when my maid will
go to the Philippines Consulate for
processing her contract
So cheap the airticket fee, I just bought a round trip ticket through agency (Philippines Airline) 0-30 days to my maid, the amount is HK$1,870 + HK$325 tax, total HK$2,195.