Thank you for your patience all this while. The fix of the issue is now part of InDesign’s latest update, Id 13.1
Update your InDesign through Creative Cloud app to Id 13.1
AbhinavPadmini Mirchandani commented
Hi Abhinav - I have the 13.1 update. But I still have the problem.
The full Pages panel does not show, esp the last 2 pages. Scroll bar doesn't show till I click on it.