^CSB usually manifests as a drive train judder at first under acceleration, first only under hard acceleration but as it gets worse even light pedal will cause it. Then as it gets worse it will start knocking or clunking, getting faster as accelerating because the driveshaft is wobbling.
I've never heard bearing whine/groan from the CSB, but that might just be I've never noticed it until the physical judder and thudding starts.
I think if your last bearing doesn't cure it I'd start listening to the diffs to see if they are making the noise.