Any advice about pages assigned to a Mastery Path being deleted without intentional action by an ID, instructor, or student?

I'm working with a few courses that use Mastery Paths. In each path, students complete a MC quiz as a pre-assessment. One item that is then assigned is a "study guide" page. The instructors have titled these pages as "Boost Your Success!" Each have been assigned to a Mastery Path sequence. IDs have verified that the pages are included and the Mastery Path is set up correctly.

However, we'll find that the pages in that Mastery Path sometimes disappear without rationale. In the screenshot attached, you'll see that multiple items were deleted at the same time; but IDs took no intentional action to delete the page. These pages are all assigned to the Mastery Path. There are no other issues with the course. Is there a reason these pages would delete themselves?

Additional notes:

• There was no instructor activity in the course when this occurred. The course did not have students assigned yet, so there was no student activity either.
• This course was built through the course import through a mastery shell. The setting "Enable individual learning paths for students based on assessment" is selected.
• The Mastery Path was tested in the Test Student area. It was present before running the Test Student.