ZETA have qualified for playoffs imo.
Here are the upcoming ZETA matches
ZETA 2-0 TLN
ZETA 2-1 PRX
ZETA 2-1 TS
ZETA 2-0 T1
ZETA 0-2 GENG
That would make them 7-2 in the league which is 3rd place.
If they win opening match in playoffs, their next match would probably be against Gen.G which is a higher chance of winning than DRX. If they'd win against Gen.G they get upper finals and get third place for Tokyo. That'd be the ideal way of qualifying.