How do I repair my cracked shower pan?
You need to fall out of love with this pan - it is broke.  Why would you want to go through all of this work and compromise your work with a broken pan?  This is a decent size project - GET A NEW PAN.  If you want cheap get a used (unbroken) pan off of craigslist.  These pans are not that much compared to how much it will cost you to do this again.