I solved this by passing the exact path of the model file without the bucket name in the start string
rasa run -m path/model --remote-storage aws --enable-api --log-file ./rasa_api.log --verbose --port MYPORT
rasa run -m 0.0.0/nlu-20220309-154118.tar.gz --remote-storage aws --enable-api --log-file ./rasa_api.log --verbose --port MYPORT