That's quite a few targets and mostly ranged attack capable. By the time Berthold closes the distance to his first adversary, there'll have been 8 ranged attacks against the vanguard. Our experience with the skeletons back with our older party suggests that we'll be pincushioned into a halt. So yeah, splitting them might be a good strategy, but as we do that, they might just slaughter the travellers.
If we could cover a part of the distance moving through the woods undetected, we might take them by surprise. Then close on a pincer move, flanking them from both sides: a couple of melee combatants on the left (say, Berthold and Sora) and a couple on the right (Antonius and Kazzak) , supported by ranged attacker -- Amnestria (left), Dell (right) and Morton (on either side).