Hi Stefan, I hope you're doing well!
The interruption related to PSWITCH in the KW36 can be enabled in the way you describe. However, by default, the DCDC configuration on the KW36 board does not use the PSWITCH SW4:

To configure the DCDC to use the PSWITCH, you will need to physically cut the 2-3 connection on J38, and solder a jumper header to short 1-2 instead.
Please let me know if you need any more information.
Best regards,
Sebastian