I appreciate you taking the time to share your concerns with me, purplehyssop. I recognize the urgency of refunding your customer, and I'm here to ensure this is a success.  

I know how this situation can be challenging. Since you have confirmed that the transactions did not appear in your Merchant account, I recommend contacting our Payments team. Our team of experts can provide additional confirmation on the payment transaction and guide you through refunding your customer.

To connect with our experts, please follow these steps: 

1. In your QuickBooks Online account, go to the Help menu.
2. Hover to the Search tab, then click Contact Us.
3. Type in a short description of your issue or concern in the box provided.
4. Press Continue. Pick the Chat or Callback option.
    

For future reference, you can check the deposit speed for your product to learn when QuickBooks Payments deposits your customer's payments. 

Directing you to our expert team will ensure a smooth refund process for your customer, purplehyssop. Keep me posted for any updates. I'm always here to help you. Take care and stay safe!