Macmini 5.1-Mid2011-A1347-Core i5-2.3Ghz-EMC 2442

Well, it looks as though the read you got from your original chip is corrupt. It does not have any identifiable modules in it at all. The one that you pulled from the purchased chip however looks good and is clean. It has a serial number in it, which I find odd because they usually do not have an actual serial number in it. If you pass me your serial number I can modify the file for you to use, but at this point I think your programmer is acting a bit funny. I think it is inconsistently reading/writing the on-board chip probably due to a poor connection or voltage. ISP is a bit tricky sometimes, so we need to step back and reevaluate the situation. I hate to keep going back to this, but I still think you should give the pi a go if you have one available. I know its a bit out of your comfort zone, but I do know its almost a sure fire way to do this. With the exception of the 1466 model MBA sometimes, which can also be tricky. I do remember having issues with consistant reads when I used the bus pirate so I can offer you a bit more advice on narrowing the problem down. Be sure that your USB cable to programmer is a good one, I mean a thick cable that is short usually works best. Companies who sell cheap programmers dont intend them to be for ISP usually and skip out on providing decent cables. be sure it is connected to a USB 3.0 port if available or at least a 2amp USB 2.0 port. It will be hard to know when the programmer is acting right because you have overwritten your original chip now, but to ease your mind the Mac is not bricked yet. All you have to do is follow what i am telling you and try to write the chip when you feel like the setup changes you have made are correct. After flashing the firmware I give back to you, you will need to do as you did before and power the Mac on and off a few times to get it to turn on likely. After every write you do make sure to go back and verify the chip, as that is your best bet for verification. I will be on a bit later if you have any further questions.

I feel 100% confident that the setup or programmer is at fault. Whenever you get the pi in please let me know and we will get back to flashing your mac.

Haha, you are so anti pi I like how persistent you are! I am glad you worked this out in the end and hope you will stick around even though our personalities clash a bit;)