The easiest place is on the dashboard, but maybe that was added in a version newer than yours.
You can also find it in the Karaf console.
But more importantly, which version of the zwave binding are you using, and how did you do the inclusion? If you’re not using the development version, then your mesh is not doing a nightly heal. And if you included the device close to the controller and then moved it, you will need to do a heal to get the routes straightened out. So it might not be just the distance. It also sounds like you are moving the devices around… mains powered devices should not be moved or it can make a mess of your mesh. It’s best to include them in their final location. If it really is a range issue, don’t waste your money on a repeater. Spend the same amount on a mains powered device that actually has some functionality. There’s a recent discussion here.
This is likely related to this, so an upgrade may resolve it.
PS, please use code fences!