I'll give an opinion :-)
First question, though, before you go on to the rest of this...what happens on the other end (external party) when a call gets transferred there? Does it go into a queue and wait however long the usual wait time is before routing to an agent on that end? If so, then you can't have the call sit on hold in PureCloud for that 4 minutes or whatever in a loop, then transfer over--then the caller would end up on hold for 8 minutes, since the call was not waiting in queue that whole time.
It depends on how you want to trigger going to the transfer functionality--automatically, based on something you can query from the PureCloud Data Integrations action, or manually (like flipping a value in a Data Table and following the behavior there).
Also, I'm wondering if the external party happens to have an API you could query with a Web Services Data Action integration action...maybe find out the estimated wait time from them to set the hold time on your side?
Anyway, with a manual setting I'd probably use a Data Table and have a value to pull back of, say, "TransferExternal" and let it be set as either "true" or "false" (or "yes" / "no").
Query that in the main Inbound Call flow, and if true then use a Transfer to ACD action to put it in a special queue that has no active/available agents which will send the call into the associated In-Queue Call flow. In the In-Queue Call Flow you can set up to play your audio prompts to let the caller know of unusual wait times, estimated wait time, etc. The Hold Music action lets you
Play for duration, so you can set how long the caller hears hold music before it moves on the the
Transfer to number. (Keep in mind, the call is not in the other system, so any hold time here is
in addition to the hold time at the other end outside of PureCloud).
So, I'll place the caveat again...I'm thinking the way you have it worded to wait on hold in PureCloud the normal amount of wait time in external queue will just double the wait time and not achieve what you really want.
I'm not sure I've helped you much, but it gives you some options, maybe.
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George Ganahl CCXP, GCP
Principal Technology Consultant
Genesys
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