Question about log on the 7th

Okay, so I see what seems like it is RH and SB going in at 9:03 and leaving at 9:53. There is another out listed at 4:28 for SB and I am guess RH. When did they go in for this second visit? Is it thought that they snuck back in or is this where a false name was used to gain entry and then sign out with their own names? Somebody set me straight here please.