the Pocahontas show at DAK is not a traditional meet & greet spot. for reasons I won't go into here, it's up to her if she wants to do it or not, but it's usually not.
characters do show up around the hat at scheduled times in MGM, but it's random. today I saw Mary Poppins with Mr. Penguin, Jasmine, Chip & Dale, Minnie, Lilo, Alice, maybe a couple of others.
I will stick by my advice. Your best bet to see both of them is exactly where I mentioned them in my initial response. If you see them elsewhere, great, but I only mentioned reliable spots.