I have exactly the same issue
I ran the diagnostics and got the same outpus aswell
I play C&C RA3 with origin, i heve the ultimate collection and use the C&C online starter.
My friend and i can invite eachother and do verything but when we want to really start the game my friend or i get that same message
"Connections are in progress, or connection problem detected. Please wait for the connection to finish, or kick the player who has the connection problem. Connection in progress: 1 - 2."
Pls help
Regards, Ferry