Add some more debugging tips

[markcmiller86]

Description

This was the result of a comment in #19888

I also fixed a problem with local variable shadowing/aliasing I ran into.

Type of change

• [ ] Bug fix
• [ ] New feature
• [x] Documentation update~~
• [ ] Other

How Has This Been Tested?

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• Please perform a self-review of your code before submitting a PR and asking others to review it.
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Checklist:

• [ ] I have commented my code where applicable.
• [ ] I have updated the release notes.
• [x] I have made corresponding changes to the documentation.~~
• [ ] I have added debugging support to my changes.
• [ ] I have added tests that prove my fix is effective or that my feature works.
• [ ] I have confirmed new and existing unit tests pass locally with my changes.
• [ ] I have added new baselines for any new tests to the repo.
• [x] I have NOT made any changes to protocol or public interfaces in an RC branch.~~