I have checked with DataDirect Support team and got reply saying below:
The Connect for ODBC SQL Server Wire Protocol driver currently does not support ‘Always Encryption Option’ option for SQL Server 2016.
We do not have a work around at this time. This new functionality will be added to the next driver release, Connect for ODBC SQL Server 8.0 driver which is scheduled for early 2018.
Please try to add in future release as soon as possible.
Informatica GCS Team