The Final Experiment (https://www.the-final-experiment.com/) essentially did this by inviting "prominent" flat earthers to Antarctica to witness 24 hours of daylight. Very few did, but they are now shunned by the true flat earthers.
When I was doing my student teaching, one of the teachers in my department was a creationist, but he didn’t seem to have read Genesis 1 at all because when I asked him about the firmament in the heavens separating the waters above from the waters below, he had no idea what I was talking about. At least the flat-earthers know enough scripture to follow their dogma all the way to its absurd endpoint.
Notes:
0 - https://rationalwiki.org/wiki/Flat_Earth
1 - https://rationalwiki.org/wiki/Crank_magnetism
2 - This is why religions such as Jehovah's Witnesses require members to proselytize (including going door-to-door) because outsiders are so adverse to the members that the other insiders remark things like "those outsiders are so depraved, that's why you can only be with 'true believers' like us".