Data entity can be only created for table that has a natural key. So perhaps this explains why Microsoft hasn't created entity for this table. The natural key is needed to determine whether an insert or update should be performed when data is imported using the entity.
You can't add natural key to an existing table using extensions. So in this case you would need to develop a new table, that would be a copy of the vendor certification table, but which would also have a natural key. The natural key (unique index) can for example consist of all fields in the table.
Then, create entity for this new table. Now you can import data to your new table. Finally you need to develop some logic that iterates your new table and inserts the data from your table to VendCertification table.
