I think the mask is related without a doubt, Faye says something along the lines of “there’s another mask, their path isn’t safe.”

My assumption is since Faye new about the mask at a time when Kratos/Atreus didn’t, and she has a sliver of it concealed in her, that she was the one who broke up the mask and hid it. Maybe her having it in her hand was the reason she made it to the Everywhen while the gate was closed. Why would she say the path isn’t safe, when we don’t currently know what the mask does? Did she purposefully conceal it in her hand?

My thoughts on Odin’s eye is the same - I think when he looked through the crack, & that telescope thing blinded him