2 weeks in a row now I have gone to do the daily adventure at Lush Reed Island and 2 weeks in a row the event ended with no contribution. First time the event was over in like 40s before I could even get a hit out, this week in spite of hitting many people…no kills or assists. This ends up with getting credit in Compass but no credit or reward for actually taking part.
A bit late to this topic, but I had same issue today. I went on daily island with my Gunlancer, which is shit class in world PvP (slow low DPS with basically no push immunity, with totally useless shield mechanic for PvP content (it break in one hit from anyone)) so I normally fought, got few almost kills, but always someone snatched it or simply CCed me and destroyed me before I went up (try to complete against Summoners, Sorcs and Gunslingers). My guess is, that I simply did not get any kill and therefore this stupid Island did not give me contribution. On other PvP islands as far I know you got assist points, here I got nothing and what is worse, it counted Island as completed even without giving me any reward.
So I basically wasted my time and 800g, which is annoying, because I have to plan around stupid Island spawns which are from some unknown reason just few times per day and in same time like another 4 events… Also they are exactly in raid times, instead of start few hours earlier.
Thanks for the thread revival, it’s certainly annoying that the contribution is different to other islands. I’ll file a bug report for the team! 
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