Update: finally got an email from Google:
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"Your file "<filename>" contains content that violates Google Drive's Phishing policy and hence, some features related to this file may have been restricted. If you think this is an error and would like the Trust & Safety team to review this file, request a review below.
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I got access again. And now it's actually being reviewed. What a terrible experience, it disappears and is inaccessible for an entire work day with no recourse. Not sure if this post caused the review/notification.