Grimsqueaker

Only if you consider the tendrils a kracken! If you consider them in the context of weirwood roots it makes far more I sense.

I really don't think so, If you look at the description of the greenseer with the one red eye and the tree roots weaving in and out of his body, it's a pretty close description of Moqorro's vision. I think the sea bit is a red herring to point to the greyjoys.