Do you see the SIP.JS extension in FreeSwitch if you run: show registrations
Also I wouldn’t expect to see a channel of type “[error]” in the log.
2023-11-28 14:04:42.951275 97.17% [NOTICE] switch_ivr_originate.c:3049 Cannot create outgoing channel of type [error] cause: [USER_NOT_REGISTERED]
Get a cheap PBX in a box with a couple of WiFi enabled phones, so it will be completely stand alone, and you won’t need to run ethernet.
Something like a Grandstream UCM6300A or a Sangoma PBXact 25 will do the job.