Shower basin drain

[Tonebone]

Pulled up a cracked shower basin and found this drain set up. I’m on a concrete slab here in Texas. After I break up this mortar bed, what do you think about this large opening for the drain, and the potential lack of support for the basin in this area ? Thanks in advance.

 

[havasu]

Easy fill with gravel.

 

[Twowaxhack]

Break out more concrete, Dig it all out and relocate the trap in the proper location. Eliminate those fittings you see. Do what it takes.

Fill with sand and pour in some quickcrete bag concrete mix