The Zwave toolbox shows me the hops between the node and the toolbox sitting right next to the hub so it gives me an idea of what the hub is doing assuming the two controllers picked the same or similar routes. I wonder whether your FortrezZ water flow device keeps wanting to use a troublesome node nearby. Given the number of devices you have it is likely that it has many paths to the hub so I wonder why it is not trying other paths. Could the device be getting overwhelmed with the traffic? Have you tried to powercycle the device to restore it?
The red lines are most likely sleepy battery zwave devices, if not, then they are devices with issues (not my case).