Sorry for the bump but i wanted to put my imput.
To start off, the first Donkey Kong game i ever played was indeed DK64, and at the time i didnt know Dixie exist. A few years later, i found a Donkey Kong Drawing book at a book fair and my mom bought me DKC2: Diddy's Kong Quest on the SNES. I immediatly started to ask questions. "Who is she?" I thought it was Tiny, but then i read more into it and found out that it wasnt. It was Dixie.
I later did a lot more research on it and found out the Dixie was Tiny's big sister and wasnt included in DK64(at that time, i havent played it much but i played it enough). I was kinda upset. I was all like "Why not? Why was Tiny there but not Dixie. Dixie could have at least been a supporting character or something. Why did they just replace her like that?"
Dont get me wrong, i love Tiny, but I was still highly upset that Dixie wasnt even considered. When i read more into it, i saw that the concept of DK64 was originally just gonna be anyone who was in DKC1, but bended the rules when Wrinkly was added. So i guess DK64 was just Nintendo and Rare's oppritunity to introduce more Kongs into the family instead of bringing back others, maybe to see how it worked out. It was obviously a success since the game was great, but there were still fans(including myself) upset the Dixie didnt get a chance in the game.
But thats just my imput, but what i woud really love to know is if someone asked the storyboard artists where was Dixie during these events, how would they answer it?