Liquid won their LCQ a lot more dominantly. They were already a top team (just barely missing out on Berlin), and the addition of Nivera was just a direct upgrade. They also won Red Bull Homeground, which had all the best EMEA teams in it.
C9 on the other hand, didn’t have a consistent form. At the beginning of LCQ they were playing pretty poorly, throwing 4v2s, and losing to Rise. They only turned up towards the end of the event. It’s more of a question mark if C9 will keep their form in Champs, especially with 3/5 (I think) of the players having no LAN experience.
Of course anything can happen. Liquid may choke again and C9 could dominate, and I do think that a lot of people are underrating them, but Liquid are more favored to do well given recent performances.