Process of removing mold from behind shower tile

Background

Thanks to a shifting foundation, the tile in one of our showers cracked along a corner and water got in behind it. We know that at the least the wall behind the tile has fails as it caved in when I leaned on it while cleaning.

We have had a few handymen tell us that the job is too large for them, and at the moment licenced contractors are describing this job as "too small" unless we want to do an entire bathroom remodel.

I've had one handyman offer to install a new surround if we do the demolition and mold abatement ourselves. So my question…

Question:

What is the process for safely removing the tile, wall board and potentially compromised framing elements and abating the remaining mold in a residential shower?