Agreed. I know she never wanted to be anyone's symbol. 

I'm thinking she and Haymitch could be a hiccup because things never go according to plan. I think Katniss would catch on to the secrecy between Gale/Prim and the other victors before Haymitch, so maybe we could throw in an argument, or have them kind of placate her and tell her nothing is going on? When they eventually do escape, Katniss would be reluctant to trust them and it would put some strain on those relationships?

No, I think that would work. We could reason that Peeta was supposed to arrange the pick up, but he got taken before he could follow through on his end, so they're stuck in the wilds and waiting? We could bring in Effie or Cinna, or even Plutarch through that because one of them could enact the final step of the plan.