Hmmmnn....if it is data which you require, I, the man Gongenzaka, can at least offer myself as more than my state as fellow 'poisoned'...

I, the man Gongenzaka, am able to...'feel', to an extent, the souls of others. More typically, this is for tracking matters, but...

...this ability has also proven useful in detecting damages to the soul as well. In particular, it is how I, the man Gongenzaka, was able to tell that Sans and those with me in the Prince's clutches, were so terribly affected by it...