There must be some good narrative reason for the bloody conjouritis, we know he can sneeze living things into existence from the spiders, so why not Sue whom he brought forth once before?. It gives a call back with a purpose and explains the stupidity of the disease, it only exists to bring back Sue.
Who knows, a bit of soulfire and Sue might be a permanent attraction next time Harry takes Maggie to the Zoo, she asked Harry in Zoo Day whether he liked dinosaurs.
Harry is going to need a larger hankie.