Yes, Goodwin was instructed to make a list within three days. So, the people being snatched that night seems premature. It is probable that more than one group exists on the Island and are at war or competing to gain control of the castaways. We know that there was a dispute between Dharma and Hostiles. So maybe there are still some Dharmas around recruiting themselves some new members? Or maybe there were two distinct groups of hostiles that lived on the Island when Dharma arrived and they were caught in the same situation .....being snatched up or recruited against their will.