Ghislaine Maxwell asked a number of his friends to contribute birthday wishes. I can easily imagine Trump saying he was busy and asking her to write it for him. I really don't think he would have wanted to be left out of that group of important people.
I personally doubt it would occur to him to use the word "enigma" in any communication. And if it did, he'd misspell it. And probably capitalize it.
I also very much doubted he'd have drawn a picture of a naked woman or anything else. But who knew? He likes to draw stuff to be sold at charity affairs, Usually buildings. But then as someone on TV said, what straight man has never tried to draw a naked woman?