In that attached thread, Nick actually goes over what should
probably go into each of the fields.
If you are going to attempt to manually provision an unsupported set, it is hoped that, you at the least, have a basic understanding of SIP, and know what information is required (and where it goes), for a set to register, given the information, that 3CX provides, when you create a new extension.
You might want to have a read through this, as a starting point...
https://en.wikipedia.org/wiki/Session_Initiation_Protocol
Unless the originator of that thread (or someone else, familiar with the Samsung set), comes forward, with more information, on how they made out, you are probably on your own, to do some trial and error.
If you are not using a locally hosted 3CX, then the set would also probably have to support STUN, which I suspect it won't.