I did that, and it DID give mc all of the previous servers, but still none worked. Creating a new one did the same thing as in the root account, just doing nothing when I press the start button.
Wait! for some reason an un updated version of java 7 was installed, which is not compatible with bungeecord, so I just installed JRE 8 update 91 and EVERYTHING WORKS AGAIN! I had done
apt-get update before, but it didn’t update java I guess.
That simply updates the sources, which will also find updates for installed programs/scripts, and in order to update these programs/scripts you must use
apt-get upgrade but I personally prefer
apt-get dist-upgrade as it updates everything and you have less problems usually.