how am i allowed to get to western area?

  •    Answer - visit DATS to see the npc that may take u for the train station.its inside the lower part ofDATS
                   - then speak to starmon and the man Digimon Masters Tera will  take u towards the western area
    D)- when u have a very digimon  level 33 go to oil refinery-3 ......yes instantly to oil refinery -3   and go obtain the dexdorugreymon's there, those DMO Tera gives a whole lot of exp. SHOUT and say LFP lv33+  DEX, in case lucky a celebration will invite u and kill those DEX until u reach lv46 digimon