This is a very expensive hobby when you don’t know what you’re doing. I’m trying to create a virtual 3-way switch for kitchen island pendent lights whose only switch is next to the kitchen sink as far away from any door as you can get. I planned to place a virtual 3-way switch across the kitchen at the entrance way from the dining room. I replaced the standard single pole switch with a Leviton DZ6HD–600 Watt Z-Wave Plus dimmer. I then installed a Leviton VRCS1-1LZ 1-Scene Controller at the entranceway. I was able to include the DZ6HD dimmer into my SmartThings network and can control it fine from my ST app; however I am unable to include the 1-scene controller directly from the ST app. I purchased a VRUSB installer USB stick and downloaded the software from Leviton only for the software to tell me that the inserted stick is not supported. Leviton customer service recommended returning it for another one (in process, but I suspect there’s a batch of knockoff Leviton sticks that are out there and I’m likely going to get another one). I have read other posts citing success with a “minimote” to include the controller in the ST network and then using a Z-wave tweaker handler to set up the association between the controller and the dimmer. I have scoured the internet but it appears the minimotes have been discontinued and I can’t find one anywhere. Honestly, at this point I would be happy just having the controller in the ST network and having ST hub handle turning on or off the light based on events signalled by the scene controller, but I can’t get ST to include the scene controller. Now I’m hearing Leviton also offers a remote programmer for $200 which will be able to set up the association, but there has to be a better way? Can I get there from here without spending more than another $50?
The Problem here is that zwave local scene controllers just don’t work well with SmartThings. There is quite a bit of discussion in the forums about the what it takes to get them set up and included. But honestly, you’re better off just using a regular no load auxiliary switch designed for virtual three-ways if that’s all that you need it for. The following is popular and works well with SmartThings.
https://www.amazon.com/Gocontrol-Z-Wave-3-Way-Accessory-Switch/dp/B00EAY3K5Y
I’m tired today, so I don’t really want to go into a whole lot of detail, but the point is that a local scene controller is designed to bypass the hub. But once you go to a smartphone app, you really want everything to communicate with the hub so that the App status will stay up-to-date. With a switch designed to be part of a virtual three-way, the switch talks to the hub then the hub talks to the master and everything stays in sync.
If you do want to continue with the VRCS1, the community – created code for the VRCS4 will also work with it, you just don’t have four buttons. ( this is a clickable link) But honestly, it’s one of the more difficult devices to use with SmartThings, and it doesn’t sound like you need it for your particular use case.
Also, before I forget: the minimote is no longer required To do associations. Nor do you need any other physical device. All you need is zwave tweaker DTH. Add your mainspowered device, in this case your auxiliary switch device, to the smartthings network. Then use the IDE to change it to the DTH for the tweaker, set the associations however you want them, and then change back to your regular DTH. The associations are saved in the firmware of the device, so they will remain the way you set them with the tweaker. 
Your post and links were spot on!! It took me awhile to digest all the technical nuances and I had to try some steps several times, but I was able to get the controller to activate the dimmer through the smart app. I haven’t tried it with the hub back upstairs in the bonus room yet, so I’m not out of the woods, but getting this far is a major accomplishment. You do good work when you’re tired.
You should see what my brain can do when I’m asleep! 
LOL!
No, Seriously…One time we had a client in a missile factory where we could only work at night and they would bring in a team of us at 6 PM and then lock us into the section of the plant that we were working on and we weren’t allowed to leave until 6 AM. They sent in lots of pizza and Coca-Cola and we went to work. We were on our third night there and I don’t sleep that great during the day so I was pretty out of it. But we had a Random outage problem we just couldn’t get solved and my boss was calling about every hour from 2000 miles away to see if we had it fixed yet. 
So about two in the morning I told the other guys, “forget it, I’m gonna take a nap.” And I laid down under a desk ( so the clients wouldn’t notice if they came through) and went to sleep.
About two hours later I had one of those absolute movie moments where I sat up under the desk, banged my head, the other guys laughed, I crawled out from under the desk and said “there’s a bad Junction in section 612.” And they just stared at me and Marcus said “we haven’t been working on section 612 .” And I said, " I know, but the local crew did a re-wire there about six months ago and Charlie’s notorious for just using push-ins instead of wire nuts, and I’ll bet breakfast it’s worked loose. "
And he had and it had and we fixed it in about 10 minutes and At the end of the shift we went to a pancake house and everybody bought me breakfast. 
Highlight of my career. LOL! 