The event is at 11 PM here, but the next day I've to catch a plane at 4 AM. So I'm not sure if I can claim those rewards. So is there any other way to get those rewards?
go to bed at 6pm, wake up at 11pm stay up til 1 am, then go to bed again, then you'll get your 8 hours sleep. apart from that. no, you must be there, maybe just stay logged in? if theres nothing yuou have to click on to get it, maybe just being logged in will suffice, though i doubt that.