Request Help - LAN JSON get request

I have spent all day reading the forum and testing different snippets of code only to make no progress and get very frustrated so I would like to kindly request any help here.

Short version:
I am trying to get a JSON string back from a local network webserver and parse it.

Longer version:
I have a raspberry pi running nginx on my local network. I can do a GET request on a URL on it and it will return an object with different temperatures. This works great in chrome or using postman/nightingale.

I am creating a device handler, not a smartapp.

The issue:
Smartthings/groovy won’t actually do the get request.
I am using hubAction to create a get request to my raspberry pi. Upon creating the request, I print it to the logging window (works maybe 10% of the time) and verify that it is correct. I then execute the hubAction. I get no errors and no calls to the parse() function. It just does not appear to do anything.

I have tried every example I could find on this forum with no luck at all. I would appreciate any guidance to put me on the right path and figure this out. Thank you.

Tagging @jody.albritton

You might want to share your code for help with this one.