Charlotte is a safe bet here as she's a Captain Level fighter. As for Ladros, it depends on how it goes. If he can absorb casual attacks little by little, he has a shot of having my vote but if Langris just pulls off an Archangel Shootdown that erases anything it touches, I don't see Ladros absorbing it, even more so if he hasn't absorbed anything beforehand. He also has a limit and a time of adaptation.
Overall, if the characters don't pull any punches and go all-out since the start, Charlotte and Langris have the most chances to win here IMO. Magna dies in the crossfire, he's not at the level of those guys (especially Charlotte and Langris). If he's lucky, he'll serve as mana supply to increase Ladros' chances of having the second place.