NOT able to connect to Teamwork using custom JSON

The 2 APIs that I need to connect to for now are as follows

1. Teamwork API 

2. Voluum API 

Both do have HTTP authentication and are REST APIs so ideally should be able to connect via your connector.

Here's the sheet and the details, not able to connect to it 

https://docs.google.com/spreadsheets/d/1U9g1L8STsJi9crXPQohCjIS1aHa5mX1BKChZT3d97Wo/edit?usp=sharing

Teamwork:

Using HTTP headers as this

{"Accept":"application/json","Content-Type":"application/json","Content-Type":"application/json", "X-Auth-API-Key":"twp_aCRfxIq4yjTDrksLL387s8f8OnTs"}