I agree with John, listing all parties to a joint account on the CTR for a withdrawal is the most conservative choice.
However, at a seminar today, one person said "the FDIC" had criticized them for including all parties to a joint account on CTR's for withdrawals. Immediately, another hand went up and that attendee said "the FDIC" had directed them to amend 54 CTRs where a withdrawal was made from a joint account and the bank had
not listed all of the joint account owners on the CTR. (The banks were from the same FDIC region.)
Obviously, these mutually exclusive pronouncements came from individual examiners who went unchallenged, not "the FDIC." Put simply, "the FDIC" isn't qualified to have an opinion, that's FinCEN's job.
Whether it's still official or not, the 1995 Guidance is all there is and its wording on withdrawals borders on nonsense. If including all parties on deposits makes sense, then including all parties on withdrawals makes sense too.
Perhaps if enough bankers contact the FinCEN Help Desk with this question, there will be something forthcoming.