2 people get “getsockopt” when trying to join my self hosted server, everyone else is fine…

If you have other people that can connect to the server, the issue is most likely networking on their side. Unless they live in a country that playit.gg blocks, or a country that blocks playit.gg. For example, my ubiquiti network at home often blocks the minecraft protocol - so somewhere to start would be to take a look at their firewalls.