Correct (well--sort of)--that's why I referenced S3-5.
I'd argue the rectal exam is really only useful for prognostication. For treatment you want to know if they have an upper or lower motor neuron bowel. But often even if they have a lower motor neuron bowel, they can benefit from an upper motor neuron bowel program. In my fellowship we typically started with UMN bowel programs for everyone. If it didn't work, then we switch to a LMN bowel program. So the rectal is really not all that helpful for treatment.
I find doing a rectal exam when patients arrive to be very off-putting and embarrassing for them--and at a sensitive time. So we often delay it if we even do it. But typically we get the info we need elsewhere--the patients are reliable at stating if they can feel bowel/bladder filling, have control, if they feel a foley or suppository get inserted, etc. The SCI research backs them up (though AIS-B patients aren't quite as reliable). And my RNs can confirm if a suppository just plops back out, if the patient is incontinent without knowing it, etc. My partner (also SCI fellowship trained) and I find that it's just rarely critical that we do a rectal exam, and typically causes more harm/discomfort for the patient, which is a lousy way to start rehab.