MDOT Send function in non blocking mode.

Calling the Send method as mentioned below in a non-blocking fashion method and I have enabled acks as well. So In the non-blocking mode what would be the expected return value of this function? In the blocking mode the return value is mdot_ok on a successful transmission or if an ack is received. So I am just wondering in the non-blocking mode, should the LORA MAC events be used to determine the success or failure of a transmission?

int32_t send(const std::vector<uint8_t>& data, const bool& blocking = true, const bool& highBw = false);

Thanks,
Yogesh