Can you check the time & date when all mods was online? If so you could just check to see who was on at the time and ask them one by one.
EDIT: I just re-read it and seen it said " members/moderators" I didn't see the members part (reading too fast) but I guess you could still do what I said.
Exactly, what I was thinking. XD
And I wonder, why you put that unnecessary comma.
I've been up for over 24 hours with no sleep. My bad -.- it isn't going to kill anyone.