Coverage w/route-to number sending to an external company

[KFLORIDA]

We are sending some calls out to an external company but if they are busy or don't answer, we want the call to stay with us. I am trying to find out if I can get any type of control with a vector step "route-to number 918005551212 cov n' for example. If my calls goes out to that external number which is a whole different company, will the call stay with my CM or come back to me if the external number is busy? doesn't answer? That is what we are looking for.
I always thought that once the call left my CM to an external number, I lost all control and it wouldn't come back. Is that true?
Is there any way for me to get the call back if the external number is busy or doesn't answer? We may have LAI available but I think that only works if you set up something on both phone systems. We only have control over the 1st phone system, not the receiving end.
Any direction would help, Thank you, Ann

 

[kyle555]

That's called 'coverage of calls redirected off-net'.

https://downloads.avaya.com/css/P8/documents/100171721

Pg 364/365:

Using the Coverage of Calls Redirected Off Net (CCRON) capability, you can use an external
number in a coverage path. The system monitors the call to determine whether the external number
is busy or unanswered. If necessary, the system can redirect a call to coverage points that follow the
external number. Any coverage point can be an off-network destination.
Use this capability for a call to follow a coverage path that:
1. Starts at the called extension
2. Redirects to the home telephone, and if unanswered at home
3. Returns to the voice mail box of the called extension

At a very basic level, you can have an external number in your coverage remote table and use that in a coverage path. There are other considerations with the CCRON feature, like making sure a 2nd call doesn't use it if a 1st call hasn't been answered. If the far end isn't answering and you get 10 calls in at once, it doesn't make sense to double down and use 10 more trunks to try the far end if the 1st call hasn't even been answered - so there's ways to fine tune it, but at the most basic level, you could very easily accomplish that.

cha coverage remote 1 - pop a number in the first field
add a new coverage path with the 1st point as 'r1' and the number of rings you want
have the 2nd point be voicemail