Scott, they are appearing in some form. We know that they aren'0t in Unova because there were no advertisement and because if they are known to appear, we will already know that from other summaries from this and other episodes. Also, we know that after this, they will be 6 Plasma episodes. However, they can appear after Episode N... specially Brock.
I have more info:
In the VA List only appears Ash, Pikachu, Iris, Cilan, Axew, Misty!!!!!!, Brock!!!!! , N and Narration. Misty and Brock will have speaking!!!! cameos. In the 14th MArch episode they aren't expected to appear but this give possiblities for the after Episode N saga.
VA taking roles in the episode:
Rica Matsumoto, Ikue Ohtani, Aoi Yuki, Minami Tsuda, Mamoru Miyano, Mayumi Iizuka, Yuji Ueda, Hiroshi Kiyama, New VA, Wasabi Mizuta(most likely = Pignite), Misato Fukuen (most likely = Oshawott or ), Megumi Hayashibara (NOT Jessie, possibly Snivy or Joy's Audino), Shin'ichiro Miki Not James, Ash's Charizard and possibly Crustle), Kiyotaka Furushima (most possible_ Excadrill), Mika Kanai (possible role = Iris' Emolga), Kensuke Sato (confirmed to do Iris' Dragonite), Rikako Aikawa (???), Hiroshi Otake, Katsuyushi Konishi, Satomi Korogi, Chika Fujimura (possible roles = Unova Joy and Ciloan's Pansage), Yuriko Yamaguchi (Japan's based region's Joy), Hikaru Midorikawa, Houchu Otsuka, New VA's , Insho Ishizuka (at least Narration (specially listed ana Oak).
The reason why you aren't seeing many role is that there will be 26 VAs in this episode. When the episodes has too many VA, the VA List only list the roles of main characters. And Misty and Brock, although they wiull have a line from the flashbacks, they will be main characters and if because they are speaking, they appeared in the VA List.
Now, the important part:
I'm not a translator and I need application that they have bad translations, but although I can't say the entire summary, Google Translate has detected the importnat part of the episode.
Ash wants to see Charizard when he see Charmander and Ash will call Oak (not Liza) to bring back Charizard. This is important because that means that older reserves could appear in Unova after Episode N's ending.