In short, yes you will be able to distinguish the incoming frames based on the sender serial.
Is the Arduino side also running in API mode? Meaning is the Arduino code already taking care of frame generation? Or the fact that data is sent to TxRx is meant to indicate that you are running in mixed mode where the XBee on Arduino is running in AT (Transparent mode?) and the Coordinator is in API mode?
In that case, the Data you send from the sensors will appear on the Coordinator as: "Explicit Rx Indicator frame - 0x91".