I’m having the same problem with your post that I have with the thread that you link to which is that what it says can’t be what exists. Eventually in that thread they figured it out but let’s see if we can get it cleared up at the beginning for you here.
First of all, every outlet must have a neutral. It won’t work otherwise. And indeed, in the thread that you linked to it is shown that there is a neutral at the outlet.
A single pole switch switch On the other hand might not have a neutral at the switchbox because the switch is effectively just a cutout of the existing circuit branch.
So let’s back up. If I understand you correctly you have an existing dumb wall switch which is wired to an existing dumb outlet. You also bought some other smart equipment but let’s not bring that into the picture yet.
First things first, as they also say that other thread, you can’t use a dimmer switch to control an outlet. It’s not safe and it does not meet US electrical code. (Unless it’s a special kind of outlet and it’s labeled and you will never plug anything else into it… Anyway that’s a whole separate thing and it’s not what you’re trying to do here.)
So let’s talk about what you are trying to do. You have a dumb floor lamp with a dumb LED bulb, is that correct? You would like to have a switch on the wall that can control that floor lamp. And you also want it to be a dimmer switch. And you want to be able to dim it from your smartthings home automation system.
Forgetting about the wiring for a moment, is that a correct description of what you want to do?