Oracle Wallet Connection setup for SSIS
When using OLEDB, I believe you should choose the Integrated Security option which would have your connection string look like this:

Provider=OraOLEDB.Oracle;Data Source=MyOracleDB;OSAuthent=1;


Since you're using wallet, you have no username and passwords.

This is assuming your wallet is configured properly in the first place, meaning test with sqlplus is positive.

I hope this helps.