The bad news is, that section was obviously plagiarized. And whoever the speechwriter(s) should be skinned!
On the other hand, of the two women, only one has clearly walked the walk, and not just talked the talk, of those words, and it ain’t Michelle Obama.
You say it’s obvious plagiarism, but I disagree. Assuming Melania is telling the truth, she wrote her own speech with minimal assistance. That means that she would have had to have been aware of Michelle’s speech and to have copied it - despite the fact that the phrases in question are common aphorisms.
How many ways are there to state you were taught to work hard, that you keep your word, etc. These platitudes are common phrases, not rhetorical crescendo.