ESP32 Determine when indication was received

I'm working with an ESP32 dev kit trying to get familiar with BLE, but have hit a wall and am not sure what you're supposed to do in this scenario.
What I'd like to do is setup the ESP32 as the peripheral device, then have it send indications (not notifications) to connected client central devices. I have looked through the BLE code and was able to find out how to use indications instead of notifications, but I don't understand how the main app I write would be able to determine when an indication has succeeded vs failed.

Here is the relevant section of the BLE library (Line 475 - 558)

Both the notify/indicate methods return void. I don't see anything which would suggest that the ESP32 would handle retransmission attempts, so how would I be able to know when to try sending it again?

Edit: I'm blind soemhow missed that there were callbacks available