Hello, @Jonathan Timmerman. I have managed to run such a script with just 2 differences:
- For us, the URL is https://frontdoor-eu.apptio.com/service/apikeylogin [I trust you know what your Frontdoor URL is 😉😉😉]
- I had the keys in separate lines AND without variables:

I remember reading how to do it with an environment variable, but it's worth a try with plain text, to prevent some funny JSON stuff.
I just tried it and it worked:

I also put the code in Python to update all the Personas in Frontdoor (vid. link), and it worked, too—after some trial and error.
#Platform