MongoDB connection inside Administration area

Hey, a client of mine wannted to use his existing mongodb inside the admin area for some content editing. I cant find a way to use Mongodb inside concrete5. Here my phpinfo:

i even tryed installing it with composer but noting changes, just default error

Any one has experience in this topic and and help me out?
This was looking promising but well not working for me Multiple Database connections needed (Mongo DB) - concrete5

Using Concrete 5.8.6

There will be a bunch of Doctrine classes to interface to Mongo from the Doctrine db layer. I suspect they are not bundled with the Concrete core.