Hi,
The MCU supports 10MHz SPI baud rate which is the fastest rate in Run Mode without the loopback option (Table 31 of the S32Kxx Data sheet).
Please note that the measurements were taken with fastest slew setting PORT_PCRn[DSE = 1] (Table 12, 13 of the DS).
So please use high-drive pins, labeled as GPIO-HD in S32K144_IO_Signal_Description_Input_Multiplexing.xlsx
Regarding EVB, I don’t see any problem with that.
Regards,
Daniel