The best way to do it, is by one of you choosing a server. Then the other do /server sg(number) Then you join the same ;3
Just like Avaline said, there is an easy way to do this! You say that your friend is in the lower numbers of hub. Make sure you are both joining the same region. For example, make sure you are both joining us.mcgamer.net (for US), eu.mcgamer.net (for Europe), au.mcgamer.net (for Australia) or ca.mcgamer.net (for Canada).
Once you are sure you are both on the same hub, you should be able to perform the command: /join sg [number] (assuming you are playing Survival Games)
Make sure there is a space between the 'sg' and the server number.
Question Answered, Thread Locked.
If you still have problems, feel free to message me.