If you have a snapshot of the droplet with all your data prior to trying to update the container, you should be able to grab a backup from that.
If not, you’re almost definitely still fine, but you need someone savvy with the process to be able to pull the data out of it if you can’t get the container back up and running.
Right now, even with the bad gateway, if you can get into the container you should be able to run a discourse backup and get your data.