I've played around with this device a lot in the past and based on what I saw in the logs and with a z-wave sniffer, the actions performed by the driver during inclusion are the same as when you click save.
If the children are missing and you click save it logs a message saying it's creating them and then creates them, but that's not happening based on your logs and I have no clue what could cause that.
If your device has newer firmware then enable the create child device for usb setting and see if that child device gets created when you click save.
If that doesn't work or you don't see that setting then you might have to remove the device and join it again. The issue has nothing to do with the device so re-joining shouldn't be necessary, but I can't think of another way to reset the driver.
I just remembered that I wrote a Hubitat driver for this device before it was fully supported by Hubitat. The driver is no longer needed, but it works fine and it might be a way for you to get the child devices without having to remove the device.
If the child devices get created with the custom driver then you won't be able to switch it back to the built-in driver without removing the device.
