I would check that if you can. The Nostr protocol requires SSL connections for WebSocekts, I believe. There may be a difference in whether clients enforce it.
Discussion
I'm connecting through wss but it's through a cloudfare argo tunnel. I have another one running at nostr.happytavern.co though with the same method and it works fine. nostr.happytacern.co uses https://git.sr.ht/~gheartsfield/nostr-rs-relay
wheat.happytavern.co is my implementation
You might like websocat. It’s a command line tool that lets you make WebSocket connections, sending standard input to it, and spitting received WebSocket message data back out to standard output.
You can cat a JSON file with a [“REQ”] message, then read back the contents, for example. There are command line flags for things like keeping the socket open. https://github.com/vi/websocat