1. Check the 10.1.2 opatch relink log (/fs/inst/apps/logs/ora/10.1.2/install/make_06102020.log) for found fatal relink errors related to /usr/lib/libcryptoutil.so.1.
Usually several binaries related to OEM will show the above fatal errors.
For these binaries the system records a warning, and moves on until it reaches the forms relinking, then rapidwiz stops without clear error message.
After setting LD_LIBRARY_PATH correctly by copying setting from a working 12.2.5 instance, the same error related to libcryptoutil.so.1 will also occur when relinking forms.
2. If you meet similar criteria as described above, check for missing symbolic links on the instance with an issue.
For example in the above case creating the below symbolic links allowed rapidwiz to proceed past the 10.1.2 home patching:
ln -s ../../lib/libcryptoutil.so.1 libcryptoutil.so.1
ln -s ../../lib/libcryptoutil.so.1 libcryptoutil.so
3. After creating the missing symbolic links, retest the installation and confirm the error is resolved.