The non existant plot line about Yoggy being the God of Death (despite the forshadowing of Saronite and the reasons the Scourge used it so much) was always a sticking point for me in WotLK. Now that we see that Maldraxxus inspired Scourge architecture despite it being inspired by Nerubians. I am wondering if there is a chance here to fix that earlier plot issue.
Could Yoggs connection to death, and maybe possibly the Shadowlands have shaped the Aqir to their spider forms and given them visions of Maldraxxus? Could this be the explanation for the similarities? While also finally giving us the hinted lore that Blizz admitted they never clearly explained (e.g. the connection between the Lich King and YoggSaron).
Another idea is that the presence of YoggSaron weakened the veil in Icecrown.