Hi,
Well, actually, you have problem with cron configuration, not with Design Studio, but I will try to help you anyway. :smileyhappy:
Could you show me the output of crontab -l command?
Please note that you should specify SHELL and PATH for cron. This is my output for this command:

with the crontab file above I was able to build the project each minutes without any errors.
And I think you can use more simple version of headless build:
#!/bin/bash
source /etc/profile
source ~/.bashrc
/home/b48014/NXP/S32DS_Power_v2017.R1/eclipse/s32ds \
-nosplash \
-application org.eclipse.cdt.managedbuilder.core.headlessbuild \
-data /home/b48014/workspaceS32DS.Power.2017.R1 -build test/Release
the project was located in workspace - /home/b48014/workspaceS32DS.Power.2017.R1
project name is test, build configuration is Release
Best regards,
Dmitry