Is it legal to have someone be the senior rater on an OER a month and a half after they left the unit?

My rater was the S-6, MAJ W. His rater was the Brigade DCO, LTC J. LTC J left the unit sometime in April. MAJ W left the unit effective 1 June, which triggered the requirement for a change of rater OER on me, with a through date of 31 May.

Having said that, when LTC J left the unit, I was given to understand that the S-3 became his rater. Now the S-3 is saying the now-former DCO can serve as my senior rater for this OER. I'm not sure how that's legal, since he departed. Can anyone shed some light on this? The regulation isn't clear to me.

EDIT: Thanks, but someone got with me privately and pointed out an interpretation of 3-58 (b) in AR 623-3. I'm not sure if it applies after the fact, but I'll take it.

LTC J (senior rater) departed 30 April. MAJ W (rater) departed 1 June, which automatically triggered a requirement for a change of rater OER on me. Because 1 June is within 60 days of 30 April, LTC J has the option of a senior rater option OER on me. Got a call into him now, hoping he'll go for that, and we can put it to bed.