BluetoothRemoteGATTCharacteristic.startNotifications() does not capture indications.

Looks from that mod like you're just responding to BLE_GATTS_EVT_WRITE in that code, not BLE_GATTS_EVT_HVC?

But I'd create a new BLE_INDICATION (or similar) enum and then do jsble_queue_pending and create a handler for it like is done for BLEP_WRITE