I've contacted a few already who this seems to have impacted directly through PMs, though just to re-iterate for other's benefit...
My sincere apologies for posting the attendee list. Had a moment where I completely forgot that the list we saw wasn't what everyone else could see.
I mis-interpreted Samh004's comment in his post, "and shall go with this, instead of updating the first post with the missing usernames" as meaning he was going to update the list in the thread with all the names, so thought I'd be helpful and send him a list comparing the two... and then for some reason thought "ah, I could just post it to the thread and Samh004 can pick it up from there...".
Realised my mistake when Samh004 sent me a PM... Thanks to Samh004 for taking it down so quickly.
So once again, my apologies to all and I didn't mean to cause any offense through the error I made.