家教會主席個女理應有一封好靚的校長信?
It depends on details. There is so much we don't know about your friend to draw any meaningful conclusion.
Perhaps we should ask this question: Where a school specifically says it doesn't want a portfolio (e.g. DBSPD), what makes you think that the school will attach any meaningful weight in reading any unwanted portfolio attached to an application?
The importance of kindergarten principal's recommendation letter depends on kindergarten's reputation and track records of the principal's recommendation. If the kindergarten's principal has some connections with the primary school that you are applying, that would be a better benefit. Otherwise, the principal may write hundreds of recommendation letters for all his/her students. Then it is of no use.