Thanks for sharing and glad you found some value in the articles. Your mother needs to understand that if you are 'fat' at 6'3" 189 then you clearly lack muscular bodyweight.
To answer your questions:
1) You may need to go to 500-550 g carbohydrate per day if you aren't continuing to gain. I also think you can probably push the fat up some more too.
2) 4000 minimum.