The command you want it:
Code:
SetCharacterRemovable(characterFromID("Danielle"), true);
You could try putting it into "PROGRAM\DIALOGS\danielle_dialog.c". Talk to her, see what she says, find that line in "PROGRAM\DIALOGS\ENGLISH\danielle_dialog.h", then find the part of "danielle_dialog.c" which makes her say that line. That is probably where you should put the command. Then talk to Danielle again and she should be removable.
To figure out the line number for the dialog text, use Notepad to look at "danielle_dialog.h", go to the line, and press Ctrl-G. That's the command to Goto a line, and by default it will show the number of the line you're on. Subtract 2 from that number. The reason is that the first line of "danielle_dialog.h" is the 'string DLG_TEXT' declaration line, and Goto starts counting from 1 but the index for DLG_TEXT starts from 0. So if you're looking at line number 10 then you'll want to find a reference to DLG_TEXT[8] in "danielle_dialog.c".