Engine missing when idling

Just so I am clear, they charged you $157.00 and didn't tell you what hose it was that was causing the issue and show it to you? Diagnostic charges are common but for that charge they are supposed to tell you what it will take to fix the vehicle. Just telling you that it is probably a vacuum leak sounds like they did not actually find the issue. If it were me, I would call the service manager and ask what you got for your money that you paid them. Just telling you that is one of the hoses or a probable vacuum leak is not what I would find acceptable for the money you spent.

The purpose of a diagnostic charge is so that people don't come to the dealer and have them figure out what is wrong and then just take the vehicle somewhere else or fix it themselves and then the dealer doesn't get paid. So they charge that amount of money to tell you what it will take to fix the vehicle. They may have done that but it doesn't sound like it is pretty clear as to what the issue is.

Here is a guide on how to find and fix a vacuum leak. Clearly that sounds pretty steep for a vacuum leak but depending on what the failed part is it is possible.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Unfortunately they don't provide a diagram on this vehicle which they normally do. However, using a spray parts cleaner around the engine looking for the RPM to raise will tell you where it is. Then we can narrow it down and figure out what part it is .