Ok, I will do one with all my findings. I notice this reference elsewhere too. Plus, I notice the base image used for the proxy is Java11, but the project is compiled with Java17, so I needed to change the base image there also.
Most of the terraform script were not working well due to some changes on the GCP API side. Also there is multiple obsolete reference to bazel and non-existing registry tool command in the documentation. I think the documentation should be rewritten from scratch. I will see what I can do.