DANG, I'VE been logged out way too long. I'm sure you have your question answered by now, and I don't even remember too well anyway, ha. Nature is hard to control, but I think you can influence it with a synchronizer. <-- don't quote me on that though.
Dust cloud are super hard to control. What you're best off doing is finding a routine that makes the dust cloud appear and then adjusting. You'll have to think on your feet. It will not advance the RNG to my knowledge. However, I've never done it because quite frankly, it's a rather idiotic task when you can breed.
I use a flash cart that supports save states. Makes wondercard abuse really easy because you only have to hit your seed once. Just save the state before talking to the man in green and check if it's the nature you want. If it is, trade it to another game and just reload the state and talk to the man in green again. Rinse, lather, repeat.
I don't think I'll be trading for a while since I've been busy with college applications. As much as I would like that chimchar, I think I'll pass for now. Maybe when I'm done with this process. Thanks anyway
I wouldn't know, but I did run your spread on PokeRNG, and apparently, the spread has a ridiculously high frame (in the thousands). Though they may not be perfect, I did find 27/31/26/30/31/30 with seed 01140227 (frame 573 with a synchronizer) and also 26/30/27/30/27/30 works with seed a60602cc (frame 42 with a synchronizer).