^Guess this is my final attack on this before i dropped this (i really don't want to feel scare every single time just opening a thread), by providing a way Touhous mights win:
So, top-tier come doing top-tier thing. The only one that could escape (momentarily) this is Reimu Hakurei (Fantasy Heaven's unpercievableness), Yukari Yakumo (Boun haxx) and... Koishi Komeji? (Unconciously non-regconize) Also the Lunar Capital-tier and Dragon God-tier. It's most likely the top tier would find time to fight the two, and be distracted enough to hatched and execute a plan.
Presumtably, they know that the top-tier power come from souls, which itself is normal, and the mysterious power that controlled by willpower. So, deactivated both of those thing, and the top tier power shouldn't work. So they grapped Yuyuko, Suika and somebody that could control emotion (in this case, Kokoro).
Next, they need to somehow "convince" Frisk (very high chance he could escape it already) to challenge the top tier like they did last time (otherwise the top tier isn't going to be immobile enough to catch). The moment Frisk tried to "save" the souls from inside the top tier, that itself would give Yukari (layed under Koishi's abilities) enough loophole to open the boundary between mind, and plunging in the team.Then it would be the matter of simutaniously sapped away the willpower that come from the souls (done by Kokoro and Suika's attraction), and maunovaring the souls itself out of the top tier.
Of course, the plan is flawed, need some major guessing and assumption that it could work, and probably isn't going to save the Touhou-verse anyway. But if it all according to plan, this would be a pyrrhic victory for them.