Transfer to Overflow Call Center

We’ve run into an issue with an inbound voice campaign.

We’re a BPO and have a client who wants us to to enable the Virtual Callback Queue, which we have done. It is currently set to offer the choice for a callback to callers when the EWT>60 seconds. The client also has asked us to transfer calls that have been in queue for >300 seconds back to their call center. It looks like the callback queue is treated the same as the regular queue so if a caller opts for a virtual callback, it maintains their spot in the queue, and if they hit the timeout threshold where their call is transferred to the overflow call center, they’re not there to get transferred (they’re just a placeholder), and the transfer fails and the “call” is dropped.

Looking for any ideas or workarounds that will allow us to use both the virtual callback queue and have the ability to transfer callers holding in queue for >300 seconds to be routed/transferred to an external number.

Perhaps use a separate copy of Find Agent block for those who chose callback, without the 300 sec threshold?

Thanks. We’re testing that now, and also using an IF block, but no success so far.