Hi Terumasa,
With your set up conditions, it clearly violates the absolute max rating for the differential input voltage stated on the datasheets and we really do not recommend that. However, based on figure 48 and 49, It shows that there is a differential protection diode and a series of 5 kohms resistors across its input. We are looking for a possibility that it may work, and maybe the datasheets just become too conservative. But I still need to confirm it to the designer or even measure it on the lab to verify this. This may take a one or two weeks but I will get back to you as soon as I can.
Best regards,
Emman