ok, I think I solved it.

Apparently, after executing commands like

sudo firewall-cmd --zone=public --add-masquerade --permanent
sudo firewall-cmd --zone=public --add-forward-port=port=80:proto=tcp:toport=8000 --permanent
sudo iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 8000

somewhat screwed up the firewall rules in the google console. The catch was that I could only acces the website from port 80, by trying to acces it from 8000(node's actual) didn't work. I deleted the rules, and added them again in the platform console (Networking->Firewall rules) and then restarted nodebb and it worked!