Need Advanced Help: System Bootstrapper has crashed

You have a Hardware problem.

One surprising issue that has surfaced in some MacBooks is failure of the SATA data cable inside the MacBook.

If you have an Apple-owned store available, your appointment at the genius Bar for an evaluation is FREE, regardless of your warranty status.

Being unable to read files needed in bootstrapping or starting up cannot be caused by additions, since none have been loaded yet.

If another drive works fine in that position, that leaves the drive itself as the source of the problem. If the drive and its cable are working correctly, a Re-Install should fix these sorts of problems.

I would use Disk Utility to first check the SMART status of that drive, then do a security erase, write Zeroes to every block (one click off the default). If it finds troublesome blocks, it will replace them with spare blocks it keeps in reserve for just this purpose. This process takes several hours for a typical modern drive.

If it passes, every block is known good again. If more than 10 blocks need to be substituted, the process will fail with "Initialization Failed!". You are free to try again for another up to ten blocks, but at some point you will no longer be willing to trust your precious data to such a drive, and it should be retired.

There are no branches and no decisions in the boot-up sequence. You did a re-Install. You tried to boot up. It died when illegal stuff was sitting in memory to be executed. That cannot happen without a hardware error.

Either the disk blocks were not written correctly, or they are not being read out correctly when you start to boot up. It is not a matter of settings, there are no settings that apply at this point in the process. It is not third-party software, because none of that is loaded yet.

So what I suggest as a next step is to do a "Deep erase" on your drive. Re-Write each and every block with Zeroes, and let it decide if those Zeroes are written correctly, and substitute spare blocks automatically. This is a very old-fashioned way of verifying that the disk has all good blocks. Most technicians would have thrown out this drive already, as a new one costs less than an hour of their time.

Run Disk Utility.

Select the troublesome drive.

Check the SMART Status for "Verified".

Choose Erase pane.

Click (Security Erase)

Move one click off the default <Fastest> to the next click < write one pass of Zeroes> ... (this will appear in the text below the slider)

>> This will take several hours <<

click ( OK)

click (Erase)

wait.