Launch external app and get back information fromjson file

1. What is the problem? Be very detailed.
I need to get som information from an external site.
In my form the user give me some information and with this informations and this external site, I get some key informations to adapt my following questions.
this site give me back a json file when I operate
Is there a way to do that woth ODK ?

2. What app or server are you using and on what device and operating system? Include version numbers.

1.24

3. What you have you tried to fix the problem?

I didn't succeed with https://docs.opendatakit.org/launch-apps-from-collect/#launching-external-apps-to-populate-multiple-fields

4. What steps can we take to reproduce the problem?

5. Anything else we should know or have? If you have a test form or screenshots or logs, attach below.