I believe this is the survey being discussed.
Some quotes from the article:
Survey results showed that 18.5% of North Korean defectors expressed that they “regret” moving to South Korea.
Those who regret settling in the South reported experiencing difficulties due to cultural differences, psychological isolation, and economic issues.
Based on her analysis of North Korean defectors’ adaptation to life in the South, IPUS senior researcher Choi Eun-young Christina explained that 18.59% of the 312 defectors surveyed who had left North Korea between 2017 and 2019 answered in the affirmative when asked whether they “regret coming to South Korea.”
Among those who reported regretting their decision, 84.48% complained about struggles with cultural differences, 70.69% with psychological isolation, and 65.52% with economic issues.
“Given that the suicide rate for defectors is over double that of South Koreans and there has been a recent rise in defectors leaving the South — including those returning to North Korea — we need to be looking more closely at the problems that defectors are experiencing in South Korea,” she suggested.