In Higurashi When They Cry Mei we get multiple hints that things are not what they seem and that they are all covered in illusions.
Ironically enough Rika is covered in the illusion of Kazuho while Hanyuu appears to be covered in the illusion of Rika.
Yes that means that Midori Kawata is Lambdadelta who shot Rika to force her to loop after Hanyuu was leeched of Blood to ascend Takano to Godhood(Lambdadelta would like nothing more than to give enough of Hanyuu to Takano to make her a God). Once Rika was dead and looping to the next Fragment while Hanyuu got sent through the Gate there would be nothing stopping Takano from drinking Hanyuu’s extracted Blood.
Lambdadelta’s plan from Gou/Sotsu/Meguri was to feed Hanyuu’s corpse(after the Soul was removed from it) to Takano but Eua derailed that by making Satoko a Looper necessitating Lambdadelta defeating Eua and stuffing Hanyuu back into her Body). Umineko has given Lambdadelta the idea of using Illusions to fool everyone while Takano makes her move in the guise of Dr. Irie.
Yes that means Hanyuu is visiting St. Lucia while Rika is forced into the role of Akari Akitake. In otherwords Akari going away is the Hinamizawa Syndrome’s attempt to explain away Rika’s trip to St. Lucia while making Satoko and Hanyuu think they are in St. Lucia when in fact they are still in Hinamizawa.
Lambdadelta appears to be targeting both Higurashi and Umineko’s settings with the Hinamizawa Syndrome with her scheme in Hinamizawa to be ascending Takano to Godhood while her scheme in the Umineko setting being to help Rosa find a Fragment where her sister Eva is still alive while Ange gets used as a test subject by Juuza Amakusa in the guise of Dr. Irie(why does Lambdadelta seem to favor Dr. Irie as the Villain anyways?).