This Issue because of, Rapidwiz is expecting a 32-bit version of the JDK, and the error occurs because the only version available is 64-bit.
Fix:
Please follow below steps to fix the issue
Copy a 64-bit version of the JDK from any 12c Oracle Home.
To resolve the issue test the following steps in a dev instance and then migrate accordingly:
1. Backup the existing JDK located in startCD/Disk1/rapidwiz/jre/
2. Copy a 64 bit version of the JDK to a zip file from any 12c Oracle Database or Grid Home located in $ORACLE_HOME/ via the following command:
$ zip -ryT 1.6.0.zip jdk
3. Move the zip file 1.6.0.zip (via scp or other) into startCD/Disk1/rapidwiz/jre/
4. Unzip file 1.6.0.zip in directory startCD/Disk1/rapidwiz/jre/
5. Rename existing 1.6.0 to 1.6.0_old
6. Retest Rapidwiz and confirm the error is resolved.