Some background information here:
In the mission Rats, your objective for the second day is to trade the Meth you cooked on the first day for information about the whereabouts of "The Mendozas" (the syndicate you are trying to take down).
On the second day, you are essentially supposed to throw bags of Meth into the back of a truck and then collect the information from a safe.
However, on occasion (which is randomly determined), the Gangsters can end up betraying your crew, leaving the safe locked and attempting to kill you.
This often seriously complicates the mission as players are unprepared for the sudden assault. In addition, you and your crew would have to drill through the safes and fend off the cops at the same time. While this isn't much of a problem conventionally, it can be on difficulties like Deathwish or if you intend to steal the Meth back.
So here is my question:
I remember hearing on a certain twitch stream that there are tells to determine whether the Gangsters will betray you. I believe it has something to do with the words that are used and phrases that are said by the Gangsters. However I am not entirely sure. This will however, allow for my crew to prepare for the onslaught and fend them off.
Is there even such a tell? If so, what is it?