Well I don't know about that, Banada Dee would be the "WTF" character like Wii Fit Trainer was, and usually a leaker would say something about all the characters, unless of course the TOS guy (assuming it's real) doesn't know every newcomer.
I'm looking at the Smash 3DS character screen to see if they can fit 6 more characters...
Ridley
Impa
Mewtwo
Chrous Men
Dixie Kong
Banada Dee
(Couldn't find a better picture so I am just using the ESRB leak)
If you move Dixie Kong next to Diddy Kong, then Zero Suit Samus will be pushed down, and that wouldn't work.
You could technically put Dixie next to Diddy, Impa next to Toon Link and Chrous Men after Mr. Game and Watch, it still wouldn't work because then the Kirby reps would be split up.
Putting Banada Dee next to Meta Knight could work since ROB would be next to Ness, moving Lucina to the end of row 5
They could technically say "screw order" and just put Banada Dee next to Meta Knight moving Little Mac to the 4th row and putting Rob next to Ness, and then Put Ridley, Impa, Dixie Kong, Chrous Men and Mewtwo at the last row and it could fit.
Edit: Wait, forgot about the Mii's, there is no way they could fit 6 newcomers onto the 3DS screen unless they split them up 50/50 onto 2 pages.
(characters with more then 1 rep on page 1. and characters that don't have more then 1 rep + clones on page 2.