Journey | Is it possible forcing the Employee to add a specific Country for National Identifier?

Hi Team
cause of integration with other legacy system, we need to force the employee to select a specific COUNTRY for NATIONAL IDENTIFIER

The employee is involved to add the info by Journey allocation and we are investigating the possibility to add a completion criteria to "force" the entering of a specific country. However it seems possible just force the adding of "National Identifier type" and "National Identifier Number":

Any suggestion to reach out the opportunity to force the employee to enter a specific country for National Identifier?

Thanks in advance!!!!
Tommaso