Personally, I would find it strange if someone modified the Pokémon and didn't do the typical Full IV. Back in 2006, there was a lot of cloning and GameShark (which could create Pokémon), but of course, it's quite rare for a PID to coincide with its seed. I don't know if any of those methods could cause this.
As I said, in all the Pokémon I have from that event, the seed is never greater than FFFF, but of course I can't guarantee that mine or the ones I've seen weren't generated. So that's the flaw. I wasn't at Moviplaya2006, but I wouldn't be surprised if it was their mistake, because it's typical of Nintendo Iberia (Spain + Portugal) to do things so badly.
Regarding the methods you mentioned earlier, “Method 1, Method 2, Method 4, Channel Method 1, Channel Method 2,” the only one that works in this situation is “Method 1 Reverse,” or at least that's the one that has worked for me. I use pokefinder 4.0.0 because I'm more used to it. In the latest version, I can't find where to search directly with Method 1 Reverse.
I realized that the Ho-ohs weren't .pk3, so I'm uploading them in that format instead.