SayHello GenServer never (re)started on `count3` node?

[Bentheburrito]

Hello, I hope I'm not doing something silly to produce this weird behavior, but I noticed while exploring the HelloWorld example that the count3@127.0.0.1 node will never (re)start the SayHello GenServer process. The following is what I get when trying to fetch the count from SayHello when only count3@127.0.0.1 is up:

iex(count3@127.0.0.1)2> HelloWorld.SayHello.how_many?
** (exit) exited in: GenServer.call({:via, Horde.Registry, {HelloWorld.HelloRegistry, HelloWorld.SayHello}}, :how_many?, 5000)
    ** (EXIT) no process: the process is not alive or there's no process currently associated with the given name, possibly because its application isn't started
    (elixir 1.12.3) lib/gen_server.ex:1014: GenServer.call/3

It doesn't seem to matter what order I start/stop the nodes, the GenServer is never moved to count3. As long as another node is online, the SayHello GenServer is started (as I've confirmed in :observer) and HelloWorld.SayHello.how_many? returns the count as expected on every node. I'm starting the nodes as recommended in the documentation (iex --name countX@127.0.0.1 --cookie asdf -S mix). Could this be an odd bug that you can reproduce or (more likely) am I doing something dumb?

P.S. I also tried adding a fourth node into the mix just in case it was some weird issue with the last node/host listed. I added :"count4@127.0.0.1" to HelloWorld.Application.*_members/0 and config.exs, but I still experience the same behavior with count3