I am a newbie too, but I believe that you got it correct.
you can test your setup by unplugging the fiber connection and see if you get a smooth uninterrupted failover, you can also watch the sessions and see which interface the sessions are routed when fiber is plugged in and when not.
I am trying to do something a bit more complex to save on SFC data
only one computer is routed via SFC, and only for Zoom/Teams/VOIP/SIP to minimize dropouts and jitter.
the other device is a VOIP desktop handset which is always routed by MAC via SFC
all other devices use “fastest response” (since I have two unlimited ISPs)
I was told not to use the SFC rules, but rather create Advanced → Outbound Policy rules
but I was also told that the router cannot do both by “IP/MAC/SSID” and “By Application”
so I came up with a scheme described here: