refactor: hide flags, improves logic around passing cluster flag in r…

[dimakis]

…egister-cluster

addresses review comments

Closes #

Verification Steps

1. Do x
2. Do y

Type of change

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Documentation change
• [ ] Other (please specify)