So, I think... I think Route 7
does not have wandering NPCs.
I went to try my hand at Route 7 with this seed because it turns out Foongus shows up there in the same encounter slot as Route 6, but when trying to find my SSF I discovered that there weren't any advancements at all. On a hunch, my next try I let the game sit for approximately a minute before Sweet Scent'ing -- and guess what, same mon. Same frame and everything.
This is good news, good news indeed. It's also notable because it wasn't on Madarame's list however many pages back; I've been using that as a bible for where to go and catch things, so this route being also good is great. Admittedly I've only tried it twice, so I'll get back to you when I've finally got this Foongus in the bag, but waiting a whole minute and not getting any PID advancements due to NPCs is pretty promising.
Edit:
I don't see why it's unhittable, maybe provide some more details about what you're capturing?
And dang, 40min for 1 month ._. *hugs my computer that spits even 3 keypress results in 10min max*
My best guess is that since NPCs call on the PID frame to see whether they move, something about frame 948 is making NPCs call on it then get a different result, causing two addition calls shortly after. So if I don't advance the frame at all, they call say twice loading in and twice while Sweet Scent'ing, advancing 4 frames. But if I advance to 948, they call twice while loading in, twice while Sweet Scent'ing, and then another two times while Sweet Scent'ing. Maybe to see which direction they're turning, and the first call was to see if they turned at all? I dunno. It's annoying, though. Hopefully Route 7 will work out better.
And the 40 minutes is probably an exaggeration. Sure felt like it, but it was probably less time. I was also searching both T0's, so that doubles the amount of time per month.