I tried to post yesterday about that bug but i couldn't, now i can but i'm at work so i've no screenshots.
I was lv 41/14 when i tried to do the quest, and what i noticed was, my CHARACTER, and only this character wasn't able to switch to another CHANNEL unless this character was in Klaipeda, your screenshots show that you're in channel 1, another post showed that the character stuck on this quest was also in channel 1.
If you try to switch from the character selection, only the channel 1 shows up, same if you're OUTSIDE of Klaipeda.
However i managed to complete the quest:
to get access back to the other channels, i just leveled up my class level to 15, then i switched class from swordsman to barbarian.
The fact that i got into another instance for this quest changed my channel, and now i'm not stuck anymore on the channel 1.
Then i went back to the quest, and done.