An alternative to the traditional copy master/detail that would solve for #1 would be to use a webhook and template field for creating the child records. It may be a bit laborious to set up depending on the audit question volume/detail. See example #2 in this blog post:
https://www.quickbase.com/quickbase-blog/how-to-build-quick-base-webhooksFor #2, could you create three checkbox fields to replace your single multiple choice. You may need some validation on the backend that the users only select a single response.
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