Can you try the unmodified command from the documentation and see, if that works?
docker container run -dit -p 8080:5000 -p 8000:8000 --tmpfs /opt/omd/sites/cmk/tmp:uid=1000,gid=1000 -v monitoring:/omd/sites --name monitoring -v /etc/localtime:/etc/localtime:ro --restart always checkmk/check-mk-raw:2.1.0-latest
I would not recommend changing the ports if you dont have to, as this will lead to confusion afterwards.