As shown in the picture, i have reached that point( south-east its the entrance to tanzan cave), but no matter how many times i entered in all the other south adventurine entrances, i just cant reach that tree with a tauros, actually i cant even find it in the first place. Im pretty sure it has to go down, since after this the path is open for the glasses. I tried hitting that log that is in the way, but the buffalant wont hit it, and i cant get there in any other way. Could it be weather based or something? Any help is appreciated