lol She sensed the whole hebi chakra in that unknown person. It didn't make sense to her. Cuz jubo and waterman was right next to her. lol"more than 1 chakra in him", you basically stated the reason why Minato couldn't sense Obito, who was fused with Zetsu.
Obito only had the 1st hokage dna in him and that only cover about 50 percent of his body.