Problem - Tethered Boot with another PC/Mac

I have even a question: I have an Apple TV2 jailbroken with the current version 0.97. Now the Apple TV2 has ios6.2.1 so that I can start only with Tethered boot the Apple TV. With my Macbook (El Capitain) everything perfect. :-)
Now I have given this my friend and he has only Yosemite on MAC. He is not getting booted the Apple TV. 2 What he has to do, so that it can boot the Apple TV? I can not always go with my him.

The ATV needs to be jailbroken on the computer that will tether it. There is no way around it.

Thanks for the answer. I thought it is possible also another computer to start the ATV. What do I do if the PC is broken and I have to buy a new one? The jailbtreak remake?

It will have to be jailbroken on the computer that will tether it… one nearby or a laptop.

I tried once to just copy the files between computers and it just didn’t work. There is a discussion of this from about three years ago but I cant find that post.