.I also doubt if it is an open-source product.
pro COBOL is from ORACLE, asking ORACLE would be the fastest way of getting an answer,
and probably also posting to one of the ORACLE Forums
asking for opinions on the overall system architecture will result in a waste of time for everybody ...
WE DO NOT BELONG TO YOUR ORGANIZATION,
WE DO NOT KNOW THE SYSTEM SETUP,
WE DO NOT KNOW
...
WE DO NOT KNOW
so suggesting to access a remote ORACLE system using DB2 DRDA would probably result in a waste of time
what does YOUR database support people have to say on the subject
anyway You/Your support might try googling with
ibm redbooks db2 oracle drda ddf