Look at the warning/error messages again. It is complaining that it failed to open the /etc/asterisk/freepbx.conf file. It fails because there already is NO such file in that location.
The error appears to be coming from /var/lib/asterisk/bin/fwconsole (line 13) which is referencing freepbx.conf at the wrong location.
There is also the fatal error under Symfony which I'm not sure what that relates to.