DDS39RF12: Synchronize multiple devices using SPI?

Part Number: DDS39RF12

Tool/software:

Hello team,

Is it possible to sync multiple devices by just using SPI?
My customer wants to use mutliple DDS39RF12 without JESD204.

From the datasheet, it seems like we need SYSREF signal, but want to make sure.

Best Regards,
Kei Kuwahara