Last thing I can contribute here it that I used the installation script command on Ubuntu.
$ /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/getAlby/hub/master/scripts/linux-x86_64/install.sh)"
Port was 8029 here.
On debian I typed in the three commands manually.
wget https://getalby.com/install/hub/server-linux-x86_64.tar.bz2
tar -xvjf server-linux-x86_64.tar.bz2
# run Alby Hub and done!
./bin/albyhub
Port was 8080