If your EVB with OpenSDA debugger can't start debug session - you can try to update OpenSDA firmware on your board.
DEBUG-OPENSDA-E200_Pemicro_v110.SDA for DEVKIT-MPC5748G
MSD-DEBUG-EVB-S32K144_Pemicro_v119.SDA for S32K144EVB
More details you can find in "Updating the OpenSDA Firmware.pdf" file. It is part of downloaded zip file from PE Micro web pages.
I tried to FRDM-KE06Z as your explaination. however, it failed programming the bootloader.
and I has a Multilink unversal FX. How to program the bootloader via SDA port for openSDA MCU.
There are only *.sda files such as MSD-DEBUG-FRDM-KE06Z_Pemicro_v118.SDA and MSD-DEBUG-FRDM-KE06Z_Pemicro_v114.SDA.