The Splintering Dark - can't complete Sentinel's Stand task

The navigation button brings me to Seysild, who only tells me to go to Southern Dreadlands. I went there, entered the shardstorm and defeated the waves with towers, then a 1-hour countdown started, I checked back after that and picked up all the drops, now it says the event is completed today and I can’t go back in, but the Splintering Dark event still shows the task as incomplete.

Oops, I posted my…

…before I’d seen this one. Same issue.

Well you couldnt guess it but it actually has nothing to do with the sentinels stand tower defense event. You have to find Seysild again in whatever zone she tells you - today was Stormpoint. There you fight a bit and its done.
Must say another mess by these AWESOME PROGRAMMERS (dont wanna be banned again for calling them not nicely…) at Blizz/Netease using the same name for 2 different events…Sad thing is I am not really suprised by this anymore…