Harpy quest has the same issue as the mines one had - does not appear in journal unless added through a token, and the quest taker still cannot enter the quest area. Cannot complete it successfully either.
In addition, the quest seems to easy given the level range and may be made more difficult. Or it is a scaling issue - for a party of 3 it would have been a proper challenge, not so for a party of 8.
The scaling for 2 is also on the easy side.
However, I am sure some of these islands are meant to be easier than others, and since it's just a chance to get, I think that's just fine.