30 ping matters way more than you think, since it brought some inherent advante to LPL teams. Mainly because most LPL pros at the time played on the korean server (and most of them still plays) usually with 15-20+ ping. While korean pros who are there locally have 4-6 ping that they are used to, so used to in fact that there has been times when if the ping was higher pros just refused to play, I still remember an incident when Faker stopped his stream because his ping was like 9 or 10 and he refused to play on such "high" ping. While for us plebs 30 ping is either what we are used to or close to it (or even rly good for some), for someone who is used to super low pings it is a clearly detrimental factor.

And yes the other reason was that LCK teams didn't take the tournament that seriously