The Culture parameter will not overwrite the date format of the Company's locale, only if the date field is being populated via a query. Master data is unaffected. A workaround would be to create a formula field on the same object the date field is on. You don’t have to add the field on your layout, just bring it in via the query. Here is the formula field’s (return type text) syntax: TEXT(Month(Date_Test__c)) + "/" + LPAD(TEXT(Day(Date_Test__c)),2,"0") + "/" + LPAD(TEXT(YEAR(Date_Test__c)),2,"0"). This formula field takes the highlighted field and populates data in the same order the Month, Date, and Year appear in.