How do I pull someone out of an already published draw

The best way to achieve this is to get the individual concerned to do this for themselves by "leaving" the event in My events.

But as an organiser, you can take this action on their behalf as follows: Locate the event in Manage draws and select the Matches tab. Here you can select any player in the event to both review their matches and, if necessary, to score them. There is also a red "force leave" button in the header of the player's match listing (on the right). Press that and the player will be withdrawn from the event.

As a consequence all their outstanding matches are aborted and byes are assigned if necessary and as appropriate.