NO PLAYBACK

According to Sony support, you should follow these next steps:
1. Ensure the batteries are fully charged or the AC power adapter is connected.
2. Remove any media (tape, Memory Stick®, DVD, etc.) from the camcorder.
3. Properly reinsert the media.
4. Ensure the media compartment is properly closed.
5. If the problem continues, try inserting different media.
In addition according to your post it is very likely that you busted the tape mechanism. In this case only a certified technician can help you.
I hope you work it out

Firstly there is no media in this camera other than a video tape. Where Sony came up with the idea there is anything else is strange. I actually own one of these babies and at $35,000 AUD I wouldn't be doing anything but taking to Sony or a recognized Sony repair center to repair it.

One thing that can cause lack of playback and record is an RF warning which simply means "dirty heads" Usually a run with a a Sony lapping tape is sufficient to solve the problem.

That grinding noise could either be the tape beingwound and stretched around the capstan etc. Or something may be caught in the main drive belt which is toothed. Again don't try a DIY job on it, get a pro to do the job.

For interests sake the camera is a Professional SP Betacam designed for ENG work. (Electronic News Gathering)