The film's original screenplay has the scene in full, along with the phonetic translation, but alas, not the actual wording.
The NATIVES SHRIEK. One of the SAILORS is DRAGGED forward, his HEAD pushed against a FLAT STONE SLAB, and CLUBBED TO DEATH.
ANGLE ON: In the midst of the CONFUSION, JACK sees the OLD SHA-WOMAN screaming at ANN. She starts chanting with rising HYSTERICS ...
SHA-WOMAN: (chanting) Larri yu sano korê ... Kweh yonê kah‘weh ad-larr ... torê Kông!
As far as I can tell this appears to be a derivative of Malay. Some of the words are familiar (korê = caused, kah‘weh = the time has come, torê Kông = Kong (the big man) is coming) whereas other parts of it seem to be gibberish.
The general implication of this imprecation seems to be that Ann and the crew have caused Kong to turn up and that she's the traditional sacrifice.