So, I do want to start into theme analysis, even though I recognize there may not be enough to inform a decision this DP. Here are the current known claims/flips for characters:
BK: Hazel Levesque
WyIted: Reyna Ramirez-Arellano
Vader: Rachel Elizabeth Dare
GP: Octavian
JoeBob: Nico di Angelo
Lunatic: Piper McLean
Notable trends - Both Nico and Piper are listed among main characters for the series. Piper is a member of the seven heroes. Nico has been instrumental in assisting the seven heroes. While it is possible that some among the other 8 characters in this game are not main characters (and it might have helped Pie to do so), I think we can assume that the majority of other characters in this game fall into one of these two camps.
So, how well do they fit? Hazel is one of the seven heroes. Reyna is one of the main characters that falls outside the seven and is key to helping them. So they both fit what we see as a developing theme for these characters. I'll say this much: so does my character.
Octavian and Rachel do not. They're both in a long list of supporting characters. Know who makes the list of main characters (not to mention one of those seven heroes)?
Frank Zhang, GP's supposed fake claim.
So, at the least at the moment, I see more reason to sus Vader and GP based on role alone. It's not a strong sus because it does seem plausible that minor characters would be in this game and the game was initially designed for 12 players, meaning that there must necessarily be more than the 10 main characters listed in his initial design. That being said, they're outliers, and it's the reason that the fake Frank Zhang claim stood out so much to me in DP1. Among the remaining characters I suspect are in this game based on what we know (or were at least planned to be before the number of players were reduced) are:
Jason Grace (one of the seven)
Leo Valdez (one of the seven)
Percy Jackson (one of the seven)
Annabeth Chase (one of the seven)
Gleeson Hedge (main character and mentor to the seven)