is there another way to stall while you get a knot undone without another yo yo?
I don’t really get what you mean by that. Try being more clear.
how do you get a knot undone quickly so you just dont stand there messing with the string
Same here. Unless he means something like “Is there a way to stall a bit while you get a knot out (in a competition) so that you don’t have to get another yoyo?”
There really isn’t a fast way. Just look at which strings go through with holes and pop them through.