As far as I know, technically speaking, using piracy-related hardware or software is not illegal - selling and distributing them is. As such, the entry point doesn't really matter if he already owns a Gateway cartridge. To draw a parallel to the United States, owning or drinking alcohol is totally legal if you're above the drinking age, but you can't sell alcohol on a commercial scale unless you have a liquor license (this varies from state to state as in some states only government-ran stores can sell alcohol, but gimme a break - it's just an analogy ).
Yeah I do understand that, but copyright laws are really weird and if there is no direct implications as to whether it was legal or not it may be easier in the long run just to keep it as "legal" as possible. I mean he could run it under gateway but explain how its done with cubic ninja for example, and just leave gateway out of it in general.