The HMC724 fanout buffer was damaged during using.

We were using the HMC724 as a fanout buffer, terminating it with a resistor pi-attenuator, and applying a VEE voltage of -3.4V. Initially, everything was functioning normally. However, after two days of use, we encountered a sudden issue where the current became abnormal.

     Upon measuring the current passing through the HMC724 separately, we found it to be 165mA, whereas the normal value should be 90mA. We are unsure of the cause. During use, I had adjusted its supply voltage from -3.3V to -3.5V, and then to -3.4V. Could this be related to the issue?

      After the damage, using a multimeter, we found that the resistance between VEE and ground was 72 ohms, and the resistance between the output port and ground was : DIP-GND 59 ohms, DIN-GND 63.5 ohms, D2P-GND 63.5 ohms, D2N-GND 2.5 ohms.and the resistance between the input port and ground was,DINP/DINN-GND 59 ohms. 

      The lengths of the output differential lines are inconsistent. I have measured a difference of 21 mils in their lengths. Is this discrepancy significant? Could this reflection cause damage to the chip?

      In addition, does the soldering temperature have an effect on it? According to the specification, it should not exceed 260 degrees Celsius. If I use a hot air gun (set to 400 degrees Celsius) to solder the chip, will it cause damage to it?

     I have attached the circuit diagram. Pleasehelp to analyze the cause. Thank you!