This is a user help forum. Getting an answer here would need some other user that has solved this issue. I do not create options pages that need to be edited regularly. If something needs to be edited on an ongoing basis by multiple people then I would likely look for a better solution than an options page.
I just did search for something, locking an options page would be the same as locking any other admin page added with add_menu_page(), which is what ACF uses to add the page. As well as any of the existing admin pages on the site. If these pages could be easily locked I would suspect that someone would have figured it out by now.
The difference here is that a post as a specific entry in the database and a flag can be added to the database to indicate that page is currently being edited by someone else. Options do not support this. All fields on any options page or any settings page are all stored in the options table and there is no mechanism available to flag all of the fields on a particular page as being edited.
This question has not gotten an answer probably because what was asked is not possible.
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