Its actually quite simple. So built into the pre there are 2 metal prongs that stick out ever so slightly. These prongs make a direct connection to 2 of the metal connections on the battery. When you get the touchstone backplate, it has a very thin plastic piece that has 4 magnets, an inductor, and 2 metal contacts that come off the inductor that connect to the prongs on the pre. in theory you would just need to have those 2 metal contacts connect to the corresponding ones on the battery. I have the parts and plan on trying this out. There is no space in the evo though, so i dont know if the backplate will fit perfectly after or how i am going to connect the contacts on the finished product. What a freaking tease that ass on youtube is.
also induction charging creates heat, and the pre was probably tested pretty thoroughly to make sure that heat didn't damage anything.