Appointing somebody a bishop is a whole different kettle of fish than naming that person a cardinal. Your average off-the-rack bishop doesn't get a vote in the next conclave.

Besides, being "orthodox" is often a matter of interpretation. I highly doubt either JP2 or B16 ever named any bishops they considered heterodox. 

(To paraphrase the old song, I say potato, you say heretic. Let's call the whole thing off, cha cha cha. 😊)