Hill doesn't think that Red Dragon would dare face Asmodeus head-on.
Being so arrogant, he must have learned somewhere that the Lord of Hell won't be coming out anytime soon... And even though Asmodeus might not fully trust it, he would certainly keep Glaysia at his side, surely she must remain in the ninth layer of Hell as well.
Hill surmised the existences around the Lord of Hell... To keep this secret until now, there certainly aren't many devils in Hell who know the news.
Even Court Steward Baalberith and Sheriff of the ninth layer of Hell, Martinot, likely wouldn't get the news... These two are reliably loyal to Asmodeus, but their relationship with Bisozeya is somewhat ambiguous.
After all, when the Queen of Hell was killed at her own place, both of them survived.
However, in the devil's concept, they truly follow the Lord of Hell, so they may battle to protect the Queen of Hell but would never choose to die for Bisozeya.
