[Paginated Report] Parameter dropdown not loading data for some users

Recently published a paginated report to the service. The report has two parameters: Region and Employee Name (in that order and hierarchy). Basically, the Employee Name will not load any data if the user did not select a Region.

Now, some users are reporting that they were unable to load any data on the Employee Name filter (but the Regions loaded just fine) however on my end and several others who I tested the paginated report with, it worked flawlessly. Is there some way I can troubleshoot this? Everyone who has access to the paginated report share the same access level and the workspace is a premium workspace. RLS is not implemented on the underlying datasource.