Sorry for my english, but I think that they are asking weather Diana is a contralto profondo, contralto basso or a different type of contralto. Because Diana is still young, and one can have both dramatic and lyric qualities in their voice, to remind the obvious fact — all people have both to some extent, for example: spinto sopranos can have both qualities equally strong.
Diana is probably a contralto, but not the lowest type. Notice that people confuse countertenors and spinto tenors all the time or call baritenor "tenor singer" just because during this one specific day and this specific performance he was using tenor technique of singing and expression.
Also, notice that spinto sopranos often have lower voices and greater/equally big vocal range than many contralto/contertenor singers (especially after menopause/reaching certain age) and contralto profondos often are able to sing lower notes, but we still name them for what they are. Your lowest/highest note alone doesn't tell you too much about your voice type, since Diana isn't even able to hit the lowest notes for a contralto, she might be at most contralto profundo or higher contralto voice.
Her voice might change in many directions. For example my own voice was lower when I was her age, but after taking certain meds that lower muscle tension many qualities of my voice disappeared because of side effects and too big dosage. When my lowest note was E2, I was told that my lowest comfortably sang note will be C2 in the near future, then after meds and other changes in life my current lowest comfortably sang note is C3. I can create lower sounds when I speak or by an accident but I don't do that in public, it sounds broken.
Later I was surprised to learn that my voice also went higher. My highest note was C7 and I couldn't sing higher than that since my early teens. I don't have too much control over it right now but since my muscles went temporary weaker over night and I had to train them from the beginning my voice went significantly higher.