I placed them there, manually.
Yes, one member did, the other was Wednesday, the day after the redis event. I will concede your contention that the two are not related.
Honestly, as I said in my PM, this is not a big deal for me, it was more of a FYI for your team. I do, however, find it strange that there is no record of them being removed from a particular user group and odd that it happened in the first place.