You are meant to save the feral Werewolf, you can't enter the cave from that entrance anymore once the fight is over, if its the start you need high agility, and to find Wuldon again, you need to save the Feral Werewolf and go into the wheat fields, try a few times, it won't instantly spawn, then the river, and finally his house. The Split Trail is just the section of the werewolf forest dungeon that can go into two different directions, try to find every path and you will find it eventually.