Hello @SumantGupta,
Sorry for the late reply. You will need to install https://nxp.flexnetoperations.com/control/frse/download?element=7557921 and https://nxp.flexnetoperations.com/control/frse/download?element=7570161, in particular
SW32N5_S32DS_3.6.3_EAR_D2507.zip and SW32N_RTD_R21-11_1.8.0_CD05_D2507_DesignStudio_updatesite_updated_D250805.zip, you will need to follow these steps for both of them:
alejandro_e_0-1760031951044.png,
alejandro_e_1-1760031982839.png
alejandro_e_2-1760032011209.png
alejandro_e_4-1760032351347.png
alejandro_e_5-1760032369121.png
alejandro_e_6-1760032393937.png
alejandro_e_7-1760032417770.png
alejandro_e_8-1760032443277.png
alejandro_e_9-1760032563791.png
After installing both of those packages you should be able to open the mex file in S32N projects in the GreyVIP.
Please let me know if you are able to solve your problem