I dunno chief, I’m pretty sure the Cayde-6 from our timeline is certainly dead. However you mentioning the Exo-Stranger stuck in a time loop made me remember that the Exo-Stranger we know tells us that she’s not from our timeline. That makes me wonder what happened to the Elsie Bray (Exo-Stanger) in our timeline? Is there even a lore explanation for that? Could that also mean there’s a chance we can get Cayde-6 from another timeline into ours? Probably not. I do miss Cayde-6, even though the D2 writing team made Cayde-6 more of an idiot compared to how he was written back in TtK in D1. But I guess with his voice actor Nathan Fillion being busy with other acting jobs, Bungie probably thought it would be better to kill of Cayde-6 instead of having Nolan North continue to voice Cayde-6 until Nathan Fillion could come back to reprise the role. That and Bungie probably decided to cut cost as well.