Veremount's reaction is completely natural. If my grandson died with evidence pointing to a rival's power, I would react the exact same way. As a Top 10, an attack on his bloodline is a direct insult to his authority. Framing isn't obvious from his point of view because Kayden and the Patrick family were already on terrible terms, especially after recent events. Calling him stupid ignores basic human emotion and political context. It is better to direct that frustration at the villain orchestrating the frame-up rather than the character being manipulated. (Usual manipulation plot of authors btw)
No hate #-.-)

Is grandpa stupid??? It's so obvious that kayden is framed.. Like how easily they got traces of his power.. And given kayden's personality.. Why would he kill a kid who's clearly weak that him... Like dude's is literally obsessed with fighting strong people. Smh