Disclaimer: I own nothing
Quick summary: Maybe I rushed a little bit chapter 10 and probably it wasn't so clear how Elliot and Olivia got found and saved. I had it pretty clear in my head but I guess I didn't manage to write down all the steps.
This is how it worked in my mind: in chapter 9, Elliot calls Fin for about 7 minutes (as we see in chap 10). I wrote down only a part of their conversation 'cause I moved back to Olivia and Cisco. The part with Elliot talking to Fin ends with Elliot saying "write down these names", which are the names of the couples leaving for the USA so that Fin or whoever, can get in contact with the local police and tell them to check. Of course, in the part not shown because I was back at Olivia, Elliot would tell Fin all about Cisco and their trip in the morning (as Elliot said he would do in chapter 8)
Plus, before going to Mexico, Fin told them to keep in contact everyday and they did (even if it's not written; at the beginning they wouldn't have much news for Fin, they just suspected Cisco; so I thought it would be useless put part of conversation to say nothing really), then since the problem with the flowers and the possibility of a bug in the phone, Elliot and Olivia wouldn't call back (to avoid their cover being blown) and that's why always at the phone with Elliot, Fin goes "you guys didn't call for two days".
At the end of the call, Elliot says he would call again Fin at 6.00am. That night they stay at Cisco's until 1.00am, then they go back at the hotel, sleep, and let's say that somewhere between 3.00 or 4.00am they're kidnapped.
They wake up when the sun is shining already so it's clearly a lot after 6.00am.
So since Elliot had to call at 6.00am and given the critical situation, at home, Fin & Co. worried. Let's say Cragen called 1PP, since THEY wanted the undercover operation, and 1PP would call the Mexican police. The Mexican police would go check at the hotel, arrest Cisco and "talk" to him. He would tell them the location where Elliot and Olivia were taken and it ends as we know.
So that's how it was meant to be. I agree, maybe there was too much "reading between the lines" but watching SVU for 12 years taught me to infer things and the story behind the twists so I just portrayed the story as an SVU episode where we don't see every step of the investigation.
Sorry again if there was confusion.
Now I'll continue with chapter 11.
