I just thought of this with your video, if you have your students submit a draft before and after they had the help of the AI you might be able to see how they were able to utilize the tool better.
Not if you tell it to specifically give you recommendations to improve your writing or content but tell it NOT to rewrite it for you. If it rewrites it for you or does the edits for you and you just copy/paste, that would be plagiarism. But if you have it give you feedback like "This was a run-on sentence" or "This paragraph needs edits to active voice" or "Your conclusion needs to integrate more of your ideas," it isn't inserting any words for you so it should not show up as plagiarism or AI generated content. That is one of the problems with both Grammarly and Quillbot right now (both excellent tools for proofreading), but if you just go through and click to accept all of the suggestions, it WILL flag the plagiarism checkers and AI checkers.