A same report run by different person, but produce different result.
1. Record visibility issue (sharing setting)
negative, because Organization-Wide Defaults is Public read-only
the user even can open the record not shown in his report.
2. Role Hierarchy filter
negative, this is not Opportunity report.
The report is filtered with a fix date (not relative date). Date in the record is based on User Time Zone setting, and this date applies to reporting too.
User 1 report
User 2 report
User 1 account
User 2 account
User 1 time zone setting is Singapore (GMT +8), while user 2 time zone setting is PST (GMT -8). If you see in the last 2 screenshots, user 1 see the record is created on 28-Feb-2018, while for user 2, it is created on 27-Feb-2018, this will cause the report have different results run by different users.