Originally the error being displayed was:
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"ARERR [552] The SQL database operation failed. : The operation could not be performed because OLE DB provider "OraOLEDB.Oracle" for linked server "{Server Name}" was unable to begin a distributed transaction." 
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for which the following article was applied:
Remedy - Server - Error when updating to a linked Oracle DB from ARSystem MSSQL database using Direct SQL action on a Filter

This error got solved but then the reported error below is observed:
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ARERR [552] The SQL database operation failed. : Unable to start a nested transaction for OLE DB provider "OraOLEDB.Oracle" for linked server "{Server Name}". A nested transaction was required because the XACT_ABORT option was set to OFF.
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To resolve this error:
"Unable to start a nested transaction for OLE DB provider "OraOLEDB.Oracle" for linked server "SAST". A nested transaction was required because the XACT_ABORT option was set to OFF"

Follow the below steps:

1- Follow the article:
 Remedy - Server - Error when updating to a linked Oracle DB from ARSystem MSSQL database using Direct SQL action on a Filter

2- Select properties of the OraOLEDB.Oracle provider:

           


3- Check the following provider options;
           - Dynamic parameter.
           - Nested queries.
           - Allow inprocess.
(Note: this article's solution worked with only those 3 selected)

          

4- For after retrieval and updating of a linked server, follow the options as per below.

• Select properties for the linked server (For case the linked server is SAST but the actual server name will be part of the error message)

               

• Check the Options as per below: