My view is The south Koreans view of china in general is negative but that isn't as bad as poll suggest. Sometimes the polling questions can be very misleading. It does not differentiate the type of disapproval.The problem is deeper here. South Koreans don't like China. Therefore anything China does other than just shutting up will be made a hysteria by the ruling party and will be used for more escalation. This is what happens in a democracy.
The stories of China's relations with countries like South Korea and Australia are tragedies. They are stories about how you can be a great trading partner (some problems happened but there was consistent exponential growth which is what matters) and politically passive but still disliked for ideological or ethnic reasons. And how that dislike can easily determine government policy.
Are SKns negative view of china the same as theirs towards Japan? The country that actually colonized, raped their comfort women and suppressed their culture? I very much doubt so.
Besides the largest foreign student contingent in china is from SK. Not sure now after covid but I reckon it's not far off. Many SKns also live in China. You can find Tons of videos on YouTube made by SKn studying or visiting or living or married to chinese guys in china, documenting their lives there. Interestingly, not as many by Japanese in even with bigger home population.