Get notification template message as a string

Summary

Get notification template message as a string

Content

We have a requirement to sent an email notification triggered by SR creation to multiple recipients.

The custom field on SR object of type [Choice List (Dynamic) <PersonProfile>] is not accessible through Object workflow => Email Notification as a recipient.

I tried to proceed with adf.util.sendNotification(java.lang.Object,java.util.HashMap) function in the trigger.

1. def map = new HashMap();
2. map.put("Channels",["ORA_SVC_EMAIL"]);
3. //def templateMessageAsString = ?
4. map.put("MessageText", "This should be templateMessageAsString variable");
5. map.put("RecipientPartyIdList",[CustomContact_Id_c, PrimaryContactPartyId]);
6. adf.util.sendNotification(adf, map);

Question: Is there any way to get the email notification template message as a string and pass it a a