Why did my vehicle stop switching into any gears?

I have a 2003 Chevy Tahoe. My first problem was
that my shifting cable broke. When i removed the
shifting cable it was binded up and looked as if it
pulled out from where it plugs into the
transmission. I bought a new cable and replaced
the entire cable. Once i replaced the cable, it was
very difficult to switch the gear from park into
reverse. Once i put it in reverse it switched
perfectly normal into all the other gears from
neutral all the way down to 1st. I tried adjusting the
cable, and was still having that same problem. A
couple weeks later i reversed out of my driveway
and tried switching gears into drive, but i could not
switch the gears oast neutral. It would only go into
park, reverse, and neutral. I reversed into my side
yard and put the truck into park. When i went under
the my vehicle to see whats going on. I noticed a
bolt missing from the rear side of the neutral
safety switch. Also the housing on the switch was
cracked. I bought a new one but I have not put it on
yet, because the next problem i noticed is the rod
that goes through the hold of the neutral safety
switch freely moves when you manually turn it. I
dont feel it catching or switching into any gears? I
dont understand what is causing that to happen.
Any suggestions? I really need help. Please and
thank you.