Its also possible that rillian is working under a time limit here. For example, whatever method he is using to hide these ruins from a fricking archmage may only last so long, and he NEEDS them to be gone before then. As an example from another story I read, there are a group of good guys, one is a young potential spellcaster that will be very powerful, and the other is an incredibly experienced spellcaster sent to protect her. The two main characters are a couple of warriors.

The two spellcasters are being targetted for death and they need a way to escape. They can use magical stealth, but apparently it leaves a small blank spot in scrying attempts, so if the bad guys know generally where to start looking, (and they do) then they can look carefully and find that blank spot. So the two warriors offer to have the experienced spellcaster create an illusion that makes it look like they decided to stick together, while in reality the two mages sneak off while stealthed. By the time the spell fades a couple days later, they are so far apart from each other that, as the spellcaster puts it, "it would take a special kind of miracle for them to find us." After all, theoretically, the actual targets could be anywhere within a 40-80 mile radius, and that is a LOT of area to cover scanning foot by foot looking for blank spots.

That could be what rillian is up to. Until the spell he has hiding the ruins fades, manta boy doesnt know where to start looking. By the time it fades away, if jayden and stunt are far enough away, it will be much less likely they will be spotted. Yeah there are holes in this explanation, but then there are holes in everything to do with this comic, so that just makes it more likely to be right.