Callback Request Tickets - Team Confusion & Customers Being Called Twice | Tags, Routing, or Any Other Insight Appreciated

Hey Zendesk Community! To preface this, I've already discussed this with Zendesk Support, but I'm hoping for some insight from other Zendesk users to brainstorm some alternative ideas.

We're using Omnichannel Routing and IVR, and we've enabled Callbacks on our Talk line, but our team has an average callback time of less-than 15 minutes for general support calls, and less than 7 minutes for urgent support calls. We have a relatively small team, and we're overall flexible with agents being able to step away, and/or set themselves to the Away status to work on other tasks.

We've been running into an issue where a customer will call in and request a callback, and one agent may see the ticket in our primary view (automatically generated due to Omnichannel) while working on something else, so they'll pause what they're doing to manually call the customer back - but then, if another agent becomes Available, the automated callback request will still ring that second agent to call the customer back, resulting in two of our agents calling back the same customer, usually within that 15-minute timespan. This issue also occurs if a customer places a callback request, but then decides to call us again, reaching an available agent while the callback request is already ringing another agent, resulting in a callback being placed while the customer is already being - or has already been - assisted.

Zendesk Support advised me that there is no way to change the subject, or add tags, for tickets where a customer requests a callback, to differentiate those from inbound calls that are still ringing our agents, as the tickets look identical. We also have set up an Automation to add a tag for expired callback tickets, but because Automations can only activate every hour at the quickest (and Callbacks have a 60-minute expiration timer), most solutions won't fit our general callback timeframe of 15-minutes.

Our backup idea would be to disable the built-in Callbacks, and create a faux-callback option through IVR which would allow us to tag these tickets. However, we're trying to avoid this, as it would not keep the customer's position in our call queue.

My asks here are:

• Does anyone have any other ideas for how we might be able to set up ticket routing, our queues, or our views to avoid any confusion for our agents as to whether a call ticket is waiting in the queue, or if it's a callback request?
   
• Is there any way to remove an automated callback request if our team manually calls the customer back, or if the customer calls in again?
   
• How would you go about setting up your call routing/tickets in this situation and/or what changes would you look to make to your team's workflow to avoid doubling-up on callbacks to customers?

At this point, everyone on the team has been advised to just not place manual callbacks to tickets that have the “Call with…” subject text, and to just switch their status to Available for the built-in/automatic callback, but we can't stop customers from calling in again while their callback request is already in our queue.

Sorry for the long one here, but any insight would be greatly appreciated. Thanks!