LE didn't even believe the girls were in danger, that's why they didn't search through the night. They definitely didn't believe they had been abducted and were in grave danger. There was zero chance they were going to issue an Amber Alert.
No, the Amber Alert would not have helped in this situation. There wouldn't have been any additional resources there before morning. The girls were dead within an hour and were not driven to another location, so nobody would have recognized them with their abductor.
The Amber Alert is designed for confirmed abductions, preferably with a license plate, vehicle description and abductor description. It is used for stranger abductions, like the 8 year old in Texas.
There are exceptions made on the vehicle policy... if a child is abducted from a house where the remaining occupants are slaughtered, or they are witnessed being abducted with a weapon... they are likely to issue the Amber Alert anyway. Jamie Closs, Sarah Maynard, the Groene kids and Elizabeth Smart are examples of Amber Alerts with almost no other information.
Lizzy and Lyric were younger than Abby and Libby but no Amber Alert was issued there either. It didn't meet the criteria.
It's also possible that they did know if he was in the room, but didn't want anyone else to know they knew that for sure. Think about what the reaction would have been if he had said "and he's in this room right now."
That wasn't going to work. I think he wanted to freak the suspect out but not cause him to do anything crazy if he was in the room (like shoot the place up.)
Also if they said he was in the room, they admit they know who he is and the public comes after LE for not arresting him already. That would have caused an enormous uproar, there's no way around it. I think the way they did it, let anyone who knows the suspect's identity know... we are onto you.
Now this could make sense. It could explain why the 2 BG's are different people... and why the original BG has been cleared. Perhaps CE backed up the 2nd BG sketch's witness.... that's certainly another idea.
See and I keep thinking that these girls were not your average girls. I think if they knew him, I think they'd say something identifying. Call him by name if they knew his name. Or if they just knew OF him, "oh crap it's that creepy car salesman" or something that would have given LE a clue. They were smart enough to record after all...