Yes. As noted in the instructions, Docker requires you to explicitly expose the ports that a container uses, so you would need to make sure to expose the port.
Also note that the example Docker Compose file at the bottom of the instructions shows a mapping of the internal port of 8099 to an exposed port on your host machine at port 80, so if you followed that example, you would need to access things on port 80.
I would also suggest checking the logs for your docker host to see if there are any insightful messages displayed in the logs.
And if none of that helps, you might share more details about your UnRaid Docker configuration for this particular container. I don’t personally use UnRAID, but sharing more details would be insightful for effective troubleshooting.