Well, sure it will run, but why in the world would you want to burn a more expensive fuel when you dont have to?
Besides the cost factor, Diesel has additives in it for lubrication, none in kero. Im fairly sure #1 diesel and Kerosene are the same thing, or really close.
Also pretty sure Diesel #2 is what we all buy at the pump.
If your friend were to search, they would find posts about injection pumps failing from lack of lubrication running kero with no additives.
It is used with diesel in the Winter though, to help with cold temps I guess (read that recently).
Anyway, sure he can do it, but he could treat it a lot better without trying too hard. At the very least, make sure he is adding 2-stroke oil to it.