Question about Digitus DN-19 12U-6/6 Wall cabinet

Anything built for 19" can be installed. There is also the option of installing shelves if the units do not fit or no rack-mount kits are available (simply place them on top).

Yes, everything fits in wonderfully, even small HPE servers fit in (DL20).
Just make sure that the exhaust air can go somewhere, best is to screw two 120mm fans on top, and make sure that nobody puts anything on top of the rack...