Verbatim is safer for passages you may quote or analyze, since wording and hesitation can matter. If you also make a clean version, label both clearly.
Mark inaudible passages with a timestamp and put uncertain readings in brackets with a question mark. Do not guess, especially for names, dates and numbers.
Treat it as a draft. It often mishears names and numbers, so correct it against the full recording and check its privacy terms before uploading.
Yes. Keep the original audio unchanged, because it remains the source for checking quotations and resolving disputes about what was said.
Ideally a second person checks quoted passages against the audio, focusing on names, dates, numbers and negatives, and you record who reviewed it.